misfiring after installing walbro fuel pump and harness
01-31-2009, 10:25 PM
#1
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misfiring after installing walbro fuel pump and harness Hey guys,
I don't know if you guys ever had this problem but here it goes:
I did a complete swap from an ls1 (camaro z28) to a 408 stroker. I changed everything got NGK spark plugs, 42lb (racematrix injectors), complete racetronix fuel upgrade, etc. The first time I cranked it after the conversion the car was running fine except I had to rev up the throttle position so the car wouldn't turn off. Thinking that perhaps it was a tuning issue so I drove it to get it tune. It was driving fine, not much idling though but it was ok. After I picked it up the car was acting funny like sputtering but not that much except when I was getting close my house it began to sputter more and more like as if the engine was going to turn off. The tuner told me to get rid of the stock fuel injectors and get a new fuel pump. So I did and today when I cranked it again, it started to misfire and kept on sputtering. Smoke started to come of from the engine and smell and gasoline was surrounding my garage. I checked the fuel pressure and it was 70lbs so it couldn't be the fuel pressure. It turned off right away. I kept of checking over and over but I can't figure out why this happen. The only way it stays on is by pressing the gas and it still sounds horrible. How can I fix this? Why did this occur?
Please help me!
I don't know if you guys ever had this problem but here it goes:
I did a complete swap from an ls1 (camaro z28) to a 408 stroker. I changed everything got NGK spark plugs, 42lb (racematrix injectors), complete racetronix fuel upgrade, etc. The first time I cranked it after the conversion the car was running fine except I had to rev up the throttle position so the car wouldn't turn off. Thinking that perhaps it was a tuning issue so I drove it to get it tune. It was driving fine, not much idling though but it was ok. After I picked it up the car was acting funny like sputtering but not that much except when I was getting close my house it began to sputter more and more like as if the engine was going to turn off. The tuner told me to get rid of the stock fuel injectors and get a new fuel pump. So I did and today when I cranked it again, it started to misfire and kept on sputtering. Smoke started to come of from the engine and smell and gasoline was surrounding my garage. I checked the fuel pressure and it was 70lbs so it couldn't be the fuel pressure. It turned off right away. I kept of checking over and over but I can't figure out why this happen. The only way it stays on is by pressing the gas and it still sounds horrible. How can I fix this? Why did this occur?
Please help me!
02-01-2009, 07:27 AM
#3
Tell us about the injectors. You started with 42s, correct?
What size/brand did you put in?
Did you reflash the PCM for the new injector size?
That would be required, otherwise the PCM would be sending too much fuel, it would be running too rich, you would be fouling plugs, black smoke, you would smell raw fuel, etc.
What size/brand did you put in?
Did you reflash the PCM for the new injector size?
That would be required, otherwise the PCM would be sending too much fuel, it would be running too rich, you would be fouling plugs, black smoke, you would smell raw fuel, etc.
02-01-2009, 11:26 AM
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Sorry maybe I should clarify. When I first did the tune I had stock injectors and stock fuel pump. Now I upgraded to the walbro 255 fuel pump and it has 42 lbs racetronix injectors. Yeah I know its running rich on fuel, would reseting the pcm work or how do I reflash the pcm (sounds like I need to go through my tuners again).
02-01-2009, 11:48 AM
#5
Yes, you need the tuner. Here are the steps you need to take:
1) Get the vehicle to the tuner (with stock injectors installed).
2) Install the new injectors.
3) Have the tuner flash the PCM.
4) Do the tune.
Steps 2 & 3 may be interchanged. Either way, you cannot run the vehicle with the new injectors without the PCM being updated first.
1) Get the vehicle to the tuner (with stock injectors installed).
2) Install the new injectors.
3) Have the tuner flash the PCM.
4) Do the tune.
Steps 2 & 3 may be interchanged. Either way, you cannot run the vehicle with the new injectors without the PCM being updated first.
02-01-2009, 12:17 PM
#6
Yes, you need the tuner. Here are the steps you need to take:
1) Get the vehicle to the tuner (with stock injectors installed).
2) Install the new injectors.
3) Have the tuner flash the PCM.
4) Do the tune.
Steps 2 & 3 may be interchanged. Either way, you cannot run the vehicle with the new injectors without the PCM being updated first.
1) Get the vehicle to the tuner (with stock injectors installed).
2) Install the new injectors.
3) Have the tuner flash the PCM.
4) Do the tune.
Steps 2 & 3 may be interchanged. Either way, you cannot run the vehicle with the new injectors without the PCM being updated first.
02-01-2009, 12:25 PM
#7
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Yeah I did had a horrible catastrophic start, ill get it down to get it tune right away. I'll just make sure there isn't any valve leaks. Thanks guys, ill keep you uptodate.
