Electrical and running problems, 97 GASE 3100.

[DCRabbit]

Hello fellow Pontimaniacs!


I have a few weird ones for you here..

Firstly, I have the same lights dimming problem when off-throttle. I rev the engine, the lights brighten and my heater fan speeds up and dash lights brighten.. I let off and they dim. It's had the alternator and tensioner replaced. Personally I think the battery isn't taking a charge well.. but it does crank very good.


Secondly, and this is a hard one.. my cars tarted running rich, and beacme hard to start. It'd have to be cranked and then would chug the odd time. And when started cold the rpms would act like I was blipping the throttle for a bit. Lots of black soot in the tailpipe.. and the occasional smell of gas when starting. HAd my mechanic check it.. the O2 sensor was going nuts.. voltage jumping, but not flatlining like it was bad. It also had a low voltage to EGR valve, valve sticking shut code. Annnd.. he says the back bank of cylinders is running lean.

He says it's the LIM.. which IS leaking oil, but not much..and my oil is fine, no choc milk look.. plus I'm not losing any coolant with no oil in the coolant at all.. No check engine light at any time and all other sensors are functioning propelry according to the diagnostic scanner.

Any ideas?

[Tebore]

If your car is still using the original battery then get a Optima redtop. The Delco battery is designed to last about 5 years, then if you don't replace it, it will take the alt with it when it goes.

You won't notice the condition of the battery just from how it cranks over the engine.

Replace the EGR, O2 and fuel filter. If you haven't changed the fuel filter then it's a good chance there's not enough fuel pressure for those old partially clogged injectors. I noticed that the car starts quite hard when the fuel filter is dirty.

Start with the basics...
Fix what's broken. Then change all the filters, Air, fuel and oil(change the oil too of course),

[Erdrickk]

dont replace the EGR valve at first, try and clean it. I had the exact same code and my cars gas mileage dropped a bit and it idled a bit rough.


I took mine off and soaked it in a shallow bath of Carburetor Cleaner and used a small pick to get the hard carbon deposits cleaned out of the corners etc...

Since I have cleaned it, it works perfect and doesnt throw any codes, my idle is good and gas mileage is back up.

The reason I say clean it first is because the damn part is $$$. I think it sells for $135.00 Canadian at NAPA. Just becareful, it has a solenoid on the top and you dont want to get that wet when cleaning the valve. GL!!!

[Tebore]

Originally posted by Erdrickk
dont replace the EGR valve at first, try and clean it. I had the exact same code and my cars gas mileage dropped a bit and it idled a bit rough.


I took mine off and soaked it in a shallow bath of Carburetor Cleaner and used a small pick to get the hard carbon deposits cleaned out of the corners etc...

Since I have cleaned it, it works perfect and doesnt throw any codes, my idle is good and gas mileage is back up.

The reason I say clean it first is because the damn part is $$$. I think it sells for $135.00 Canadian at NAPA. Just becareful, it has a solenoid on the top and you dont want to get that wet when cleaning the valve. GL!!!

It is almost a 10 year old car sometimes the EGR solenoid is dead.

But of course it's worth a try. :)

[Erdrickk]

Your right, it is worth a try because he Could possibly save $100-$150.00 for an hours time.

[DCRabbit]

Thank you for your replies. I'm calling around to try to get an Orbital redtop and every place says they don't make one to fit my car. :/

[DCRabbit]

Well, had the battery changed.. to an Exide SubZero.. an Orbital wouldn't fit. Annnnnd.... still the same problem. No difference. :P

[antoniobanderas]

off course,don't believe everything you hear,use your own judgment first of all,for the dimming problem,check engine to starter and battery for bad grounds,chances are this is it,for the other problems,first go one at at time

[Longs]

The electrical symptoms sound like a bad voltage regulator. Is the voltage regulator integrated into the Alternator on this car, or is it separate?

Good luck!
Longs

[DCRabbit]

Again, thanks to all who replied here.. I really appreciate it. Hmm.. havwe to clean off the ground to the engine. I don't know if the voltage regulator is integral to the alternator, tho I expect it is. Odd thing, tho.. with the fresh battery in, the drivability problems went away. That leads me to suspect the only thing wrong is a fluctuating voltage problem. And considering what's been done to it so far, I suspect the bad ground as has been mentioned above. Orrr.. the ECM was just running it on the base programming and as it reads the sensors in different running conditions, the problems will return.

Where is this ground located on the '97 3100? Anyone know?