Help with hesitation

[95Cobra302]

Here's the problem with the cobra. I put about 50 miles a year on it so maybe it's neglected!!! It starts up perfect and idles and revs fine, but once you start accelerating, it hessitates bad and its impossible to get up to speed. It never stalls though, so the only problem is when accelerating. The only code I got was a fuel pump circuit failure. But since I unhook the battery after I drive it the code hasn't come back. The mass air was cleaned a few weeks ago and the fuel filter, cap, rotor, plugs and wires are about 3 years old. Anyone have any ideas??

 

[Chythar]

Check under the cap on the dizzy, see if you have any metal shavings or corrosion built up on the cap or rotor. Age doesn't matter in this case, it's the proximity to the ocean.

 

[95Cobra302]

Yeah, I was thinking about checking that out. Good call. I'll take a peek at it when I get off of work.

 

[sl03gt]

Fuel pump, had similar issue, when under load felt like the car was pulling a semi, wouldn't go over 30.

 

[Chythar]

Fuel pump is a good point. Check what your fuel pressure is at idle and while accelerating in neutral.

 

[95Cobra302]

I checked the cap and rotor and it looks ugly, lots of corrosion build up on it. I'm going to change it out tomorrow. I can't get a fuel pressure gauge to hook up to it, nobody rents them out and i don't have 40 bucks to plunk down on one. But hopefully swapping out that cap and rotor will do the trick.

 

[HISSIN50]

Recheck your codes. If a FP issue is happening, with any luck you will toss a lean (o2) code.


Also check your plug wires. With that kind of age, yours might be leaking.

Make sure your TPS has a linear voltage increase as the throttle is opened. An open in the TPS can cause a miss due to the EEC thinking you let off the throttle.

And really go over your wiring. A packrat might have eaten some wires.

 

[95Cobra302]

Well I just changed the cap and rotor and no luck. It's still doing the same thing. I'm not getting a check engine light now since I always disconnect the battery. I'll have to see if it comes back on and then check the codes again. I'm really pissed, I was hoping the cap and rotor was the problem, now it looks like i'll need more time to diagnose it and more money to fix it.

 

[Chythar]

Well, the cap & rotor would have caused a problem if it wasn't part of the problem now. Corrosion ain't a good thing.

 

[tealstang67]

Well I just changed the cap and rotor and no luck. It's still doing the same thing. I'm not getting a check engine light now since I always disconnect the battery. I'll have to see if it comes back on and then check the codes again. I'm really pissed, I was hoping the cap and rotor was the problem, now it looks like i'll need more time to diagnose it and more money to fix it.

How old is the gas? I just worked on a car that never gets driven also. It had some of the same issues it turned out to be that the fuel filter was all broke down and plugged up (he said it is new 4 years old). I would definitly try to check fuel pressure. good luck

 

[95Cobra302]

Fuel Filter is about 3 years old, put a full tank of gas in it 5 months ago along with a full bottle of Stabil, fuel stabilizer. If I get some money maybe I'll change the plugs and wires and fuel filter. I've had this car almost 9 years and have never had a driveability issue, I know the car inside and out and I think that's why it's bugging me so much.