I drove my '87 GN to work this morning, no problems, cranked it up to go to lunch and noticed the idle speed was around 1300 rpm, car has always around 650 or so. Got the car home and noticed black smoke coming out the tailpipes when the engine was revved. It was running super rich. Could not get the idle down.
I put one of those rebuilt Delco MAF sensors on car two weeks ago. I have green stripe injectors and 233 fuel pressure regulator with less than 15,000 miles on them. Check engine light does not come on.
Can anyone give me an idea of what might be causing this high idle, overly rich condition? Could the rebuilt MAF be bad?
Any help appreciated.
Thanks,
Dan
To quote TurboDave, YES
Just my opinion, but a friend let me "borrow" his LS1 MAF and translator while the engine is out of his car, and it made a big difference in how my GN runs. There has been a lot of trouble with the aftermarket MAF sensors. Maybe others have a suggestion but I do not know of any good ones, I had tried to find one a while back. My MAF seemed to work ok, but I think it was going out since the idle improved when I unplugged it. And the scan numbers never maxed at 255, they were low 240's at best. With the new setup, they max at 255 immediately at WOT. There are a lot of adjustments with the translator, which does add more tuning if you mess with that. Good luck, Tim Roark
I bought the rebuilt Delco MAF from Kirban Performance, cost $189. Could not find a new one anywhere. Kirban also sells a Tomco unit, new I believe for around $90. Supposedly, these do not look the same, but are said to work correctly. Does anyone have any experience with the Tomco or should I just keep trying rebuilt Delcos? They do have a 6 month warranty.
I didn't realize the LS1 MAFs would work. What, if any mods would have to be made to adapt to our cars?
thanks again.
Dan
I have a 87 T-TYpe and it has a rough idle in the morning and you have to crank & give it alot of gas to get it started and the idile goes up and down until i warms up. If it sets after runing it awhile it has a hesitation when you get on the gas then it kiks in real good. and this all started after i had a new fuel pump put in and i had all the sensor cheked out and they are allright so the mechanic says Can some one help me.
Rob Ramirez
Rob it sounds like you need to reset the Idle Air Control valve. See http://www.gnttype.org/techarea/faq/IACreset.html
Hope that helps, let us know if it works
Rob:
Do you have a fuel pressure gauge to tune with? If so, check and see how long your car will hold fuel pressure after you shut it down. If it is less than 10 minutes and the gauge reads zero then your injectors are leaking or the check valve in the fuel pump is bad (but with the new pump I doubt it). When my stocker injectors went south on me, my GN exhibited these same symptoms. Hard starts in the morning and after driving around for a while. After the new injectors went in she starts up perfectly.
The bouncing idle could be attributed to this condition but I think mine did that with the stock chip. Do you still run with the stock computer chip?