2g Turbo Fuel and Ignition Problem

[zachakagoat]

Ok so last week my 2g takes a shit on me while I'm on a road trip leaving me stranded for 14 hours. The car drives perfect there but on the way back, early in the morning, the car has been sittin so the engine isn't hot just yet but is an extremely hot day. Ok car starts cutting out and bucking and not idleing right, so immediately I think for the worst and stop the car htinking it could possibly be the timing belt slipped or something. After towing the car home I begin to diagnose the problem and still a few questions before I start to go order new parts. I can start the car and it will run fine for about 15 minutes then the sputtering and cutting out starts. I guess this is due to either a heat issue with something electrical or something with the new injectors.

I recently installed Evo8 560cc injectors and a walbro 190

Checked timing - Dead on marks so that's ok

Fuel of oil and water - thats good

Pulled off return hose to check if enough fuel is getting to the engine and all is well there

Felt tops of fuel injectors and they are cycling so I believe they are firing ok.

Car will rev just fine in neutral but seems to hesitate at low end.
Pulled the spark plugs and they were fouled out black so leads me to believe I'm running way to rish and something isn't firing in the chambers. White is lean right? so that would mean my injectors and fuel system is in check.

I pulled the spark plug wires and began to test the ignition coil with the car cold and the coil read to specs but after we let the car warm up the numbers were ALITTLE off, not much but slightly out of range via the manual. I have ordered a new ignition coil but have not yet installed it as I want to make sure it is the problem before I install it because once installed you can't return electical parts.

Ok so today I go and start up the car with the new sparkplugs I just installed NGK BR7ES and the car idles fine for awhile. I have the SAFC set at -18 across the board because I haven't got to tune the car yet. I plug in mylogger and read the RPM, 02, and Short Term Fuel trims. The car sits and idles fine at about 800rpm. The logger reads back and forth between -1 and 1 on the Short trim so I believe that the car is in a good spot for idling for now atleast. I come inside to let the car idle for awhile, I hear it start to spudder and go outside to check on it. The short term trims are going up and up from -7 to -12 on top of me pulling -18 fuel with the SAFC. So does this mean that I'm not firing right and that the engine is pulling fuel to straighten out the o2s? This would confirm the ignition coil going out at operating temp wouldnt it?

thanks for the help maybe this discription will let someone help me out and get my baby back on the road.

 

[zachakagoat]

Also the Primary ignition coil after running to normal operating temp is dead at 0hms and the secondary coil, the one where you plug in the plug wires read around 16ohms and 17ohms. Does this mean the coil is dead? if so I'll throw this new one on if this will solve my problem.

 

[JLangevin]

It sounds like a dead coil. Since when they heat up with engine temp, the leads inside can short out, etc... If the coil did measure 0 ohm, then definitly change it.

Also, I noticed you upped the fuel pressure with the new pump, and the injectors, but I didnt see you mentioned anything about an AFPR, get one!

 

[zachakagoat]

I just installed the coil and it still is having the same problem. When I sit and let it warm up and idle out it will run fine for awhile and then it decides to start pulling fuel like crazy, an extra -10 from what my logger says. I already have the SAFC at -18 across the board so I don't know what to do. It cuts out and tries to stall out. Any ideas for me to look over that I haven't already covered?

 

[92awddsm]

Test the power tr cold and hot. It can begine to fail with temp increase also. Did you have and silly tach readings while it is missing and popping?

 

[zachakagoat]

Nothing silly just some slight popping and dropping in the idle. How do you test the power transistor on a 2g? my manual only gives me the testing procedure for the 90-94 models. And is says to use a 1.5volt dry cell batter? what is this?

 

[92awddsm]

I dont have the procedure for testing a 2g power transistor but I think it is basically the same as testing a 91-94(some please chime in if I am wrong)

And a 1.5v dry cell is a aa battery.