[Saveaux]

Well I finally put everything together today. It went much faster than I expected! To recap:

- Walnut blasted valves
- New Spark Plugs (gapped to 0.032, light coat of copper anti-seize, very light coat of dielectric grease on the inside wall of the boot)
- PAW Intake and TB spacer
- PAW TCM Tune (requires sending TCM to PAW)

I went to start the car and....drum roll....nothing! The engine doesn't turn over, nothing.

I reinspect everything, put a meter on the battery, it reads 12.5 volts.

I check the fuses; nothing obviously wrong here.

I perform the definition of insanity, per Mr. Einstein, and try to start the car several more times hoping for a different result.

There is no different result.

I'm embarrassed to admit the following...it then clicks with me....the TCM is still sitting in the shipping box I got from PAW.

I unhook the battery, install the TCM, reconnect the battery and sit in the driver's seat. I turn the key and subsequently have an engine that sparks to life.

An engine that coughs and runs rough. There is a "Reduced Engine Pwr" message staring at me. While the engines still running, it seems to clear up after about 8 seconds.

I turn it off and restarted, once again it runs rough and then clears up.

The thirds time I start the car it runs perfectly but still has the reduced engine per message. I let it idle for quite awhile.

I pull out my OBD2 reader and get the same message that it said on the car a year ago - Error.

I walk to my neighbors house whose a mechanic, since his trucks at home and ring his "Ring" doorbell. For the second time that I've ever rang his bell he doesn't answer.

Tomorrow I'll drive it to O'Reillys and try their reader and reset the code at the same time.

I've read here on the forum that it could be anything from a bad HPFP to an electrical gremlin.

I look forward to my O'Reillys trip....

Stay tuned...

 

[Saveaux]

Update

More embarrassment from me here.....turns out if you don't plug the wiring harness back into the HPFP then it doesn't like to run! I drove it around the block this morning and I'm quite sure that I can tell a definite difference with the TCM tune.

I need to call Dave Gilbert and inquire with him but I'll start with y'all first....

Since the TCM tune claims to remove the torque management system - does that mean I'm able to access more torque than previously? Maybe it's because I haven't driven the car in several months but it sure seems like my butt Dyno says that I'm being pushed into the seat much harder than I previously remember. Perhaps it's cold tires but half way through first gear I get the low traction warning, I never remember the car doing this before the tune.

 

[dan_bremen]

Hi guys, I'm new to the forum because I just bought an Opel GT. I bought the car with an engine failure (MIL). The previous owner replaced the spark plugs and coils to try and fix the problem but to no avail. After reading this post I think the problem must be carbon build up on the valves as the car has 132,000 km on it. I have been thinking about buying CRC spray to clean them but I don't know if I will be able to disassemble the intake manifold. Is it too difficult? I suppose that if I take it to a workshop it will be an expensive repair. This is what I get from the OBDII scanner:

============1==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 3 - misfire detected ============2==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 1 - misfire detected ============3==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 2 - misfire detected ============4==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 4 - misfire detected ============5==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Temporal OBDII: Random/multiple cylinder(s) - misfire detected
============6==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 3 - misfire detected ============7==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 1 - misfire detected ============8==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 2 - misfire detected ============9==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 4 - misfire detected ============10==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Random/multiple cylinder(s) - misfire detected

 

[joybill44]

Hi guys, I'm new to the forum because I just bought an Opel GT. I bought the car with an engine failure (MIL). The previous owner replaced the spark plugs and coils to try and fix the problem but to no avail. After reading this post I think the problem must be carbon build up on the valves as the car has 132,000 km on it. I have been thinking about buying CRC spray to clean them but I don't know if I will be able to disassemble the intake manifold. Is it too difficult? I suppose that if I take it to a workshop it will be an expensive repair. This is what I get from the OBDII scanner:

============1==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 3 - misfire detected ============2==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 1 - misfire detected ============3==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 2 - misfire detected ============4==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 4 - misfire detected ============5==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Temporal OBDII: Random/multiple cylinder(s) - misfire detected
============6==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 3 - misfire detected ============7==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 1 - misfire detected ============8==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 2 - misfire detected ============9==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 4 - misfire detected ============10==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Random/multiple cylinder(s) - misfire detected

Are the cylinder misfire codes the only codes indicated?

 

[kgschlosser]

iif you are going to do a valve cleaning the best way to do it is to take the intake manifold off the car and rotate the engine so you have the intake valves closed on 2 of the cylinders. then you can use a spray designed to loosen the carbon. fill up the ports where the valves are closed and wait 30-45 minutes, soak up the liquid with some bllue shop towels (they won't come apart when they get wet) then using a pick tool and a small flat headed screw driver losen up as much of the carbon as you can. then suck the debris out with a shop vac. repeat the process until the valves are clean. then rotate the engine so the other 2 cylinders valves are closed and do the same thing. This is the best way to clean the valves..

 

[dan_bremen]

iif you are going to do a valve cleaning the best way to do it is to take the intake manifold off the car and rotate the engine so you have the intake valves closed on 2 of the cylinders. then you can use a spray designed to loosen the carbon. fill up the ports where the valves are closed and wait 30-45 minutes, soak up the liquid with some bllue shop towels (they won't come apart when they get wet) then using a pick tool and a small flat headed screw driver losen up as much of the carbon as you can. then suck the debris out with a shop vac. repeat the process until the valves are clean. then rotate the engine so the other 2 cylinders valves are closed and do the same thing. This is the best way to clean the valves..

Thank you it looks a little intimidating for someone that has never opened an engine but I'll give it a try.

Are the cylinder misfire codes the only codes indicated?

Yes, cylinder misfires are the only codes found, in fact I copy-pasted all the report here. As stated previous owner changed spark plugs and coils and I don't think the problem is the injectors (there are misfires in all cylinders) so I suppose problem should be lack of compression caused by carbon deposits.

 

[JohnWR]

Thank you it looks a little intimidating for someone that has never opened an engine but I'll give it a try.




Yes, cylinder misfires are the only codes found, in fact I copy-pasted all the report here. As stated previous owner changed spark plugs and coils and I don't think the problem is the injectors (there are misfires in all cylinders) so I suppose problem should be lack of compression caused by carbon deposits.

If you suspect that the valves are causing a loss of compression you should do a compression test or, better, a cylinder leak-down test.

Cleaning the valves is not without risk, and you can cause additional damage if you do something wrong.

It is always best to know what is wrong before trying to fix it.

 

[kgschlosser]

does the car start and run at all??? if there was a severe loss of compression on all cylinders the car would have a really hard time running.

on the back of the engine between the engine and the firewall more on the drivers side of the car, there i a ground wire attached to the back of the block ta the ground off and give the connector on the ire a good cleaning with a wire brush and also the spot on the back of the block that it is bolted it. then reattach it.

give that a shot...

 

[JohnWR]

Hi guys, I'm new to the forum because I just bought an Opel GT. I bought the car with an engine failure (MIL). The previous owner replaced the spark plugs and coils to try and fix the problem but to no avail. After reading this post I think the problem must be carbon build up on the valves as the car has 132,000 km on it. I have been thinking about buying CRC spray to clean them but I don't know if I will be able to disassemble the intake manifold. Is it too difficult? I suppose that if I take it to a workshop it will be an expensive repair. This is what I get from the OBDII scanner:

============1==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 3 - misfire detected ============2==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 1 - misfire detected ============3==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 2 - misfire detected ============4==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Temporal OBDII: Cylinder 4 - misfire detected ============5==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Temporal OBDII: Random/multiple cylinder(s) - misfire detected
============6==============
P0303 Raw code: 0303 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 3 - misfire detected ============7==============
P0301 Raw code: 0301 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 1 - misfire detected ============8==============
P0302 Raw code: 0302 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 2 - misfire detected ============9==============
P0304 Raw code: 0304 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Cylinder 4 - misfire detected ============10==============
P0300 Raw code: 0300 ECU: Unidad de control del motor Estatus: Confirmada OBDII: Random/multiple cylinder(s) - misfire detected

A member of the forum has posted repeatedly about solving engine problems by greasing the o-rings on the two MAP sensors and on the EVAP solenoid to stop air leaks that were causing problems for him. The codes were not the same, but an air leak could cause misfires, and it is both cheap and easy to do so it is probably worth trying. Checking all of the intake connections to make sure there are no leaks, and that nothing is broken is also a good idea, although that should have been one of the first things checked, even by the previous owner.

Does the engine have problems running, or is the MIL the only indication of a problem?

 

[kgschlosser]

what I am finding odd is that there are engine misfire codes but no codes for the o2 sensors. if it was a spark related issue or a coil related issue even a valve related issue there would be unburnt fuel getting into the exhaust and this would cause a DTC to get set for the O2 sensor readings being out of range.

It could be your HPFP. you would need to check using your code scanner. go into the Live Data screen and look for the fuel pressure at an idle it should be above 700 to 1200 at an idle and when you increase the RPM's it can go as high as 2500. if you are increasing the RPM's and you see it drop to bellow 1200 then chances are you have an issue with the HPFP

and when running the car it can go as high as 2500 but typically no lower then 1200. If you see it dropping low at random times

 

[JohnWR]

what I am finding odd is that there are engine misfire codes but no codes for the o2 sensors. if it was a spark related issue or a coil related issue even a valve related issue there would be unburnt fuel getting into the exhaust and this would cause a DTC to get set for the O2 sensor readings being out of range.

It could be your HPFP. you would need to check using your code scanner. go into the Live Data screen and look for the fuel pressure at an idle it should be above 700 to 1200 at an idle and when you increase the RPM's it can go as high as 2500. if you are increasing the RPM's and you see it drop to bellow 1200 then chances are you have an issue with the HPFP

and when running the car it can go as high as 2500 but typically no lower then 1200. If you see it dropping low at random times

This is why i asked if there were symptoms other than the code. A misfire will trigger a code long before the O2 sensor will detect anything, especially for an intermittent problem. The problem could also be in the crankshaft position sensor.

 

[GXP08jrf]

I'd check for more simple things 1st including incorrect spark plug or gap, bad ground connections (particularly on the left front of the engine), loose terminal at the fuel injector connector (to main engine harness), bad gas or any loose or disconnected/damaged pipe/tube in the induction system resulting in water ingestion before you attempt the maintenance discussed in this thread.

As the OP indicated 2 years ago at the start of this thread (although I may have mis-read) there is no complaint other that seeing the build up. No claims of codes or lost performance from the OP nor from any of the 100+ of responses. I think you have something else going on that would surely have a more simple solution. I think sending you off perform work that you've never done before with a high potential of causing additional harm is irresponsible before eliminating the other potentials. You need to do the diagnosis yourself and not trust the PO on the service or diagnostic history.

In addition to carbon build up, there are several Bulletins for misfire as alluded to above that are relatively "simple" checks.

 

[kgschlosser]

The "new" OP, the one with the Opel GT has posted scans revealing that there are DTC's that have been set. These DTC's are misfire codes. Now the fact that there is a misfire code for each cylinder is a clue. The new OP also mentioned that the coils and plugs have been changed. so we can rule that out. The ground for the coils is not on the front of the engine. It is on the back of the engine as I have described a few posts back. The new OP also asked for information on what is a good way to do the valve cleaning, I directly answered the OP's question. I do not think the issue the OP is having is caused by carbon build up on the valves. I cannot imagine that all 4 cylinders would be having misfires due to this condition at the same time. That being said there are things that are not known. At the onset of this problem before the OP owned the vehicle did all 4 cylinders develop the misfire codes at the same time? or did the last owner continue to operate the vehicle in this condition and other cylinders exhibited the same problem eventually and over time? Because the onset of the problem did not occur when the OP owned the vehicle that information is not known.

If we look at it as all 4 cylinders developed the misfires at the same time we have to think.. what can cause all 4 cylinders to do this?

Ground
Fuel pressure
Crank Position Sensor
Timing chain jumped

So what has been suggested so far for the OP to look at?

Check and clean the ground at the back of the block and check the fuel pressure. The crank shaft position sensor was also mentioned as a possibility, this would be a replace the part and see if it fixes it. To test the sensor would require the OP to have an oscilloscope, buying the sensor is cheaper then buying an oscilloscope to test it. the first 2 things suggested will not cost the OP a penny to do and are the easiest. then we get into the crank sensor and then start looking at things like the carbon build up and jumped timing

I am not exactly sure what else you feel we should go over with the new OP. Is there something we missed??? if so add it in there. This is a community that helps so any and all input is welcome. The statements you have made suggest that we have not offered information as too what can be causing the problem. It makes it sound like we suggesting things that are going to cause further problems.. and while you are critiquing me and anyone else who has responded, you offer not 1 piece of information that would help solve the OP's issue. There are many things that can cause a misfire and most of them do not have TSB's for them. Using the TSB's are the last resource to be used. All other items must be checked first and if no solution is found then check the TSB's...

Causes of a misfire
Bad Coil
Bad spark plug
Wiring issue with the coil
Bad injector
Clogged injector
Bad wiring to the injector
Crank position sensor
Low compression (caused by bad rings timing or carbon buildup)
pre-detonation

There are a few that I didn't mention but those are the major ones.

what things in the above list can cause misfire codes on all 4 cylinders?
4 coils going bad at the same time.. Never happen.
4 spark plugs all going bad at the same time.. there has to be some kind of major event like pouring a large quantity of oil into the intake for all 4 to be bad, so not likely
4 injectors going bad.. Never happen
4 injectors getting clogged.. if another major event occurred like sugar in the gas tank then yes, otherwise Never happen.
Low compression on all 4 cylinders.. only the timing jumping; carbon buildup not likely; damage to rings, piston or cylinder lining.. Never happen
Bad wiring to the injectors.. Never happen (injectors are wired directly to the ECM individually and do not share wiring between them)
Bad wiring to a coil... Can Happen (shared ground at back of block)
pre-detonation.. Not likely
crank position sensor.. Can Happen

New things that can cause misfires on all 4 cylinders
Fuel delivery (pressure)


list is now reduced to 4 things
Bad coil wiring
Fuel delivery (pressure)
Crank Sensor
Jumped timing.

I would say that is pretty well thought out and 3 of the 4 items have been suggested to the OP for things to check.

 

[kgschlosser]

@dan_bremen

I would recommend looking at other things first before tackling cleaning the valves. It is a pretty involved process to do it the right way. It's not that it is hard to do. but there are a lot of things that have to be taken off just to get to the intake. The other thing is it can take a while to do, and for someone that has never done it before it is not going to be a one day job and you have to have a good organization system for parts and nuts/bolts...

I use brown paper bags and a sharpie and write something on the bag so I will remember what it is and what the contents belong to. It really doesn't matter what you write so long as you are able to remember what it is. so when you take something off then you put it in that bag. another good thing to do is to take a photo of the piece before you remove it and write the filename of the photo on the bag as well. this way you have a reference of how the thing is supposed to be oriented. I will typically put a bolt back in the hole it came out of after removing a part, but if the bolts are going to be removed for more then 20-30 minutes I will bag them so I do not lose them. also number the bags so you know what order things cam off in and you can reverse the process. It always sucks when something doesn't get put back on in the right order and you have to take a bunch of things back apart again in order to get the one you forgot put back into place.

Couple of questions.
Can you feel the engine misfiring? does it do it at an idle or only when you increase the RPM's?
Have you tried clearing the codes and seeing if they come back?? If so do they come back as soon as you start the car or does it only happen if the car gets driven?
Is the actual check engine light on or is the light off but the codes are in the computer?
Does the check engine light flash at all when the car is being driven???

 

[GXP08jrf]

Whoa there! The 2nd OP made a conclusion, somewhat based on the 2-year-old thread, that I think was flawed (the conclusion, not the original subject) based on the same sentiments in the recent write ups. I guess what I was trying to say is that it'd be irresponsible of me, you, him and the community to "endorse" a course of action (cleaning the valves, the general topic of the original & 2nd original thread, of which no endorsement was made) when he hasn't indicated verification of other potential causes except verbatim from the previous owner (at least his is what I interpreted, maybe I missed something), hadn't yet provided additional detail on the recent recommendations nor performed a cylinder leak-down measurement (as was recommended) to help determine if the valves truly contribute to the problem prior to doing potentially more harmful maintenance. Check and re-check the "easy" stuff 1st instead of relying on the previous owner's comments and trusting his work and diagnosis especially because he lacks the vehicle's history. This is all I was attempting to communicate. Maybe "irresponsible" wasn't the best choice of word.

Bulletins pertinent to the "misfire discussion":
#16-NA-383 - covers carbon build up on the valves
#PIP4147 - covers the potential of aftermarket components (lightweight rotating components)
#PIP4197 - covers water ingestion typically in humid conditions and hard accels
#PIP4182 - covers loose ground wire on the cylinder head
#06-06-04-054 - covers potential poor terminal contact at the fuel injector multi-way engine harness connector

My error in responding was being vague with the term "maintenance" and not specifically tailoring my response from the perspective of blasting the valves, the subject of the original topic from 2019 as his "next step" and not providing enough emphasis and separation to the other advice to actually root cause the issue the 2nd OP is having. Not providing a lot of detail was my attempt to be succinct and to have the 2nd OP focus on the root cause, diagnosis and process and not the specific valve cleaning maintenance.

 

[Wunderkind]

2nd OP should start a new thread and become the OG OP.

 

[dan_bremen]

Wow I see a lot of new potential causes to check, I will have a look at those service bulletins. Today I was ready to do a compression test on the cylinders to diagnose what's wrong with the cylinder misfires. I have read that in order to do that I have to disconnect the fuel pump to stop sending fuel to the cylinders during the test. The thing is I removed the fuel pump fuse with the engine on but the car doesn't stop! It's supposed to be fuse number 19. Very strange. I'll do the compression test anyway as it will only take me 20 minutes and post the results. Today I started the car after several days and it was throwing some white smoke from the exhaust but it was water condensation, I suppose it's normal.

 

[kgschlosser]

You can do the compression test by turning the engine manually also.

 

[kgschlosser]

Oh when you do the compression test make sure you crank the adapter that is needed onto the hose for the compression tool. You want it to be crazy tight it sucks unscrewing the thing from the head only to find out that the adapter is what unscrewed and is now in the head at the bottom of the tube. royal pain to get out. Because I have had the pleasure of having to go through that before I thread lock the adapter onto the compression tool.