SUMMARY OF ISSUES:

- Poor MPG (12.4 mpg typically)
- Bogging while going from one gear to the next
- Poor/slow acceleration
- Sulfur smell while heavily accelerating or going up-hill
- Very rarely, the car will turn off while sitting at a red light



Hello and thank you for taking the time to read my post.

I've had my automatic '86 V6 Firebird SE for about 9 months now, and bought it at 88,000 miles. The car purportedly sat in a barn for about 13 years prior, and by the look of it was very well-kept.

I live in North Florida, and the climate here is typically very warm.

Initially when I bought the car, the only issues relating to gas was the smell of gas after exiting the car, and low MPG. Those issues still exist -- I get around 12.4MPG, and I always smell gas when exiting the car. I do not smell it inside the car. I do not have a lead foot.

Going uphill or putting a lot of pressure on the gas pedal sometimes does give me a sulfur-like smell coming from the front of the car which I can smell on the inside. I would believe this to be my catalytic converter, and I was curious to know if anyone thought this was related to my other issues.

I only use 100% pure gasoline in the car.

The main issue now is that the car bogs during the first 45 minutes of driving it of the day. The issue does somewhat subside as the day progresses. The car always takes twice to start -- I put the key in the ignition, turn the car on, it sounds like it starts just fine, and then it just turns off (it's as if it hits a high rpm, and then just drops, within a few seconds). I wait a few seconds, turn it on again, and it holds steady, with maybe a slightly noticeable drop in RPM after a few seconds, but it does stay on. I never have to turn it on three times. And, I normally only have to do that during its first start of the day.

I pull out of the driveway, drive a little, and then stop at a red light. After being stopped, as I proceed to make a turn, the car hesitates, bogs, revs, and then eventually moves into second gear. This happens turning over to 3rd gear as well. It appears to happen mostly when I am turning, and especially when my car's nose is pointed downwards -- surprisingly, less so while going up a hill. It does still happen though.

The car feels as though it is not accelerating at a pace that it should be. I realize it is only a V6...but I always feel bad for folks behind me because I can just never seem to accelerate well enough.

I recently (within the last month) replaced my fuel filter with no change.

Very rarely, but on more than one occasion, the car has simply turned off while sitting at a red light for no apparent reason. It starts back up just fine with no other qualms.

My question is, what could it be, and does anyone have experience with this sort of issue and dealt with it with success? I have read through old forum posts here and understand that it apparently might be my fuel pump, fuel pressure regulator, sending unit, injectors, catalytic converter, ignition module, fuel lines, fuel tank, 02 sensor, throttle position sensor, base timing, charcoal canister, and who knows what else. I'd like to narrow it down or simply hear of other's similar issues to give me a better idea of where to start. I understand, however, that if it may indeed be any of these that I may just have to pick one and go from there.

Thank you again for taking the time to read this, and for any feedback you might provide.

 

First thing you've gotta do is a fuel pressure check . If done right , it will tell you if your fuel rail is holding pressure or not , and from the sounds of the mentioned sulfur smell I'd say not . Most likely , where this sat a long time either the fuel pressure regulator being ripped or the injectors being stuck open are the reason for the rich running . One quick check you can do is to remove the vacuum line that runs from the fuel pressure regulator to the throttle body (remove it at the throttle body and leave the other end connected to the regulator) and see if that line smells of gas . If it does the regulator is bad . It's checks like these that can help pinpoint why it's running too rich and if you DO end up needing a set of injectors "South Bay Fuel Injectors" who is a member here gives a small discount to TGO members .

 

I'd be more worried about a fuel leak under the car from rusted fuel lines than running rich (car sat for years in a barn probably on either dirt or straw which attracts moisture and wet which rusts the fuel lines). That sulphur smell is usually an indicator of running lean. Has the car ever thrown the SES light while driving? Find out if there are any trouble codes. I'd guess on 44 System Lean.

Might also check under the upper plenum area for rodent infestation which can result in cut wires to fuel injectors and coolant temp sensor... And vacuum leaks.

 

Problem mine had was very similar with my 2.8 L V6. After a great deal of headache, I found the small canister the vacuum line from the throttle body went to was broken: where the line attached and starving the fuel pressure regulator of vacuum. Someone had previously used gasket sealer on it thinking this would hold. I used a strong two part epoxy to fix it. I now have full acceleration again. Key-on fuel pressure was 40 lbs. and holding when tested. With the vehicle idling and giving it gas, I could watch it stumble erratically on my gauge. I know the previous owner had the injectors and tank and fuel pump changed and this damage likely occurred during the injector repair. Canister mounted to ignition coil bracket with 10mm screw.

Cracked at the base and sealed with sealant.

Cleaned thoroughly and epoxied

Re-installation