Misfire Corsa B 1.0 2000

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xj40s
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Misfire Corsa B 1.0 2000

Post by xj40s » Sat Apr 22, 2017 11:33 pm

Hi
My son has had a Corsa B 1.0 for nearly 2 years. For much of that time it has had an occasional misfire / lack of power.
MIL light code indicates it the lambda sensor but this is the result, not the cause. This is the 3rd Corsa b 1.0 I have known with this problem and garages seem to be unable to identify the cause and make a permanent fix. The fault on my sons car has never been serious enough to make it worth putting into the garage and it passed its last 2 MOTs no problem. The fault seems to come on worse the longer the drive. Most severe was loss of power after 40 miles. I now have the opportunity to have the car off the road until 5 May and intend to sort it. My suspicion is the car is running a bit cool and a bit rich.
Any advice where to start? Coolant temp sensor? Injector?

Cheers
Tony

liviu2004
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Re: Misfire Corsa B 1.0 2000

Post by liviu2004 » Sun Apr 23, 2017 6:31 pm

Start first by visual inspection spark coil and spark plugs, check their color as well.
Not sure what engine code you have there nor how spark coil model.
This should be a simple engine.
What tools do you have available and most important, do you have a scope?

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STC
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Re: Misfire Corsa B 1.0 2000

Post by STC » Sun Apr 23, 2017 10:42 pm

Any advice where to start? Coolant temp sensor? Injector?
I have rendered your text of Coolant temp and Injector in Red - because it endangers your wallet. You are just guessing / hoping. ????

To answer your question:
Any advice where to start?[
Yep! Fault codes and Measured Values / Live Data. In particular STFT, LTFT, as a start, for a direction ....

xj40s
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Re: Misfire Corsa B 1.0 2000

Post by xj40s » Fri Apr 28, 2017 11:43 pm

I have a 4 channel picoscope and a Gendan code reader. The code reader only gives the code number with a brief description, it does not show real time data.
The engine is the 3 cylinder with all 3 on plug coils as one part. Last time I looked plug colour was fine. I have not had time to check recently.
Reason I wondered about cool / rich running is exhaust seems sootier than normal, heater is cooler than normal (so my son says) and more sludge build up than normal in camshaft cover. That is also why I wondered if it was CTS sensor or dribbling injector. I am not daft enough to play "parts darts" I was just hoping someone may know if any component in particular is known for giving these types of problems.
The fuel pump cover had been misassembled onto the tank allowing fuel to leak and possibly dirt / water to get in. I sorted this and fitted a new fuel filer.
Can I check the fuel trims with the equipment I have?. I have driven the car with the scope connected to the lambda sensor. All OK but the fault would not occur during the drive.

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TwoWaves
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Re: Misfire Corsa B 1.0 2000

Post by Technician » Sat Apr 29, 2017 6:32 pm

Hi, the other guy has gone now so hopefully no more insulting replies to requests for help. It's difficult without the car in front of me, but if you suspect the car engine is running rich, the exhaust tail pipe black and sooty maybe, and maybe you have no gas analyser to check, take the car for a good road test, make sure the engine is fully warmed up, then check by feel the bottom coolant hose, it should be hot, then the top hose, which also should be hot, followed by both heater hoses from the bulkhead, which should be hot. If the top radiator hose is hot but the bottom hose is cool, then the thermostat is closed, but this is unlikely your type of problem, if both hoses, top and bottom are cool, then the thermostat is possibly stuck open, if so the engine may not be getting to normal operating temperature, thus this could cause the engine to run richer than normal.

If any work has been done on the engine cooling system whereby the breather pipe has been removed and re-installed on the front of the timing case cover end of the engine, then it is possible air is trapped in the engine, which can be quite difficult to prime out, but I'd suspect you would have other symptoms as well. You could also check to see that the radiator cooling fan cuts in and out when the engine is hot, this would tell you that the engine is achieving around the + 90 degrees mark.

I can's say what the Gendan code reader is capable of as I don't have one, but it would be a big help to you if you could get live data read, an exhaust emissions test done, and then maybe post back the results.

Please keep us informed.

Dcunning35
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Re: Misfire Corsa B 1.0 2000

Post by Dcunning35 » Sun Apr 30, 2017 3:09 pm

What is the dtc you retrieve relating to lambda?
Id advise starting there and look at the freeze frame data for actual engine conditions at the time.
If you can post that info I can comment further rather than speculating

Danny

Datchet Diagnostics
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Re: Misfire Corsa B 1.0 2000

Post by Datchet Diagnostics » Wed May 03, 2017 9:39 pm

an exhaust emissions test done
Pre August 1992 we had this - A state of bliss.

On this car the catalyst would mask most issues. In the absence of DTC P0420 the results will be misleading.

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TwoWaves
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Re: Misfire Corsa B 1.0 2000

Post by Technician » Thu May 04, 2017 9:45 pm

On this car the catalyst would mask most issues. In the absence of DTC P0420 the results will be misleading.
Provided the catalyst has not suffered a melt down due to the misfiring engine? :mrgreen:

xj40s
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Re: Misfire Corsa B 1.0 2000

Post by xj40s » Sun Jun 25, 2017 11:14 pm

Hi
An update.
Car has now been doing many fewer shorter journeys and sludge in cambox has disappeared.
Plugs on cylinders 1 and 2 spot on -light chocolate brown. Cylinder 3 plug a shade paler but still acceptable.
To get the fault to show we drove for over 1 hour 20 minutes with laptop connected to Lambda sensor as previous stored code was P0130. The sensor output was Ok if a bit sluggish then it flatlined. Upon getting home sensor removed and the "end cap" was missing, removed catalytic converter but no sign of end cap. Removed and refitted ECU connectors working them in and out in case of poor connection.
Fitted known good (but well used) sensor, cleaned all the vacuum and breather pipes, fitted new air filter. Ran car in garage checking Cat temperature with infra red thermometer. Once warmed up voltage near constant at 0.6 to 0.65 instead of cycling between about 0.2 and 0.8. Engine gave occasional cough with sustained RPM of 3,000 to 3,500. At time of cough Lambda voltage dropped to 0.2 ish indicating mixture weak.
Fitted fuel pressure gauge. Pressure steady at nearly 3 bar.
Fitted brand new Lambda sensor - gave correct waveform. Took car for drive with 2 passengers. With sustained gentle climb (engine working hard) at nearly 70 mph MIL light came on then went out immediately as speed reduced. Car drives well with just occasional "cough" (much less than previous)
When level of fuel in tank drops a bit I will remove fuel pump and check "tea bag" filter and fit new fuel filter and try to check TPS voltage with scope. Some of the coughs occur during or immediately after rapid throttle movement.

xj40s
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Re: Misfire Corsa B 1.0 2000

Post by xj40s » Fri Jul 07, 2017 8:36 pm

The car passed its MOT with a bit of struggle to get the above idle CO within the 0.2% limit.
Prior to the test I had discovered that the manifold heating flow was blocked where it enters the header tank. Fixing this has made the throttle body much hotter but the misfire symptoms persist.
The MOT tester suggested that the Haas lambda sensor may not be as good as a Bosch even though the scope shows its working OK.
The ECU is a Bosch motronic M1.5.5, does anyone know what the fuel pressure should be?

The vacuum take off for the fuel pressure regulator is on the air filter side of the throttle butterfly. This seems strange, I thought it should be on the manifold / injector side. Any thoughts anyone?

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