[wyat]

I had a 93 3.8 cougar for a long time - has over 200K now and isn't really being used. My problem was that it had a dead spot when I'd give it gas. A very small dead spot immediately when fuel was applied. It'd sputter and even die sometimes. But once it got past the dead spot, ran perfect. The thing got 28 mpg it's whole life. Cold weather usually contributed to the problem. Also, it idled crazy sometimes, sometimes not. I replaced every sensor in the car and had it checked on the computer several times. No cure. I've tried for years to fix that problem and kind of gave up on it.

I recently bought a 91 5.0 builder and the mechanics of the car are great. Having driven it for 6 mo's now, i'm starting to notice mild symptoms similar to my 93. The ever so subtle studder right when i touch the throttle from a stop is there now? There's no check engine codes. How can two different engines have the same brain racking problem? I hope someone has experienced this and figured it out. Thanks!

Matt

 

[dwinthrup]

i would clean you maf's. you have to take it apart, take the back sensor off of the top of the housing and clean it with electric parts cleaner

 

[wyat]

i wish i could say that helped, but made no difference on both vehicles. Thanks though!

 

[dwinthrup]

can you give more info on stuff you have tried: plugs, wires, cap & rotor, check timing, sea foam, fuel filter, air filter, o2's, plugged cats, try different gas station vacuum leak, bad tps. how much of this and more have you tried.

 

[icantdrive55]

If you don't drive hard intake deposits can build up. You probably have alot of carbon on top of the valves and around the injectors. The carbon will absorb the fuel, especially when cold.

Not saying that's your problem, but likely part of it. A couple cans of carb cleaner then some new plugs fixes alot of cars with those symptoms.

Proper fuel pressure is important. The fuel filter should be changed every 15,000 - 30,000 miles. Kinda depends on if you ever buy gas at 7-11 or some hole in the wall station.

Another thing to look at is the tps. They will wear most in the location where the throttle sits the most. You can check it with a voltmeter and make sure the voltage changes smoothly. If the voltage jumps around it's 'glitchy' and should be changed.

Another thing on older cars is excessive egr flow. This can be tested by temporarily unplugging the vacuum from the egr valve.

I could go on and on but that should get ya started with the brain racking

 

[FordMan77]

I second the TPS. My 5.0 is doing the exact same thing right now and I know its the TPS, just haven't gotten around to replacing it. This is of course assuming that everything else is in working order. Prob. wouldn't hurt to replace the fuel filter as well, especially if you don't know the last time it was done.

Jay

 

[wyat]

i appreciate the help fellas. So hear goes.

On my 3.8, i changed all sensors, including egr, tps, o2... Also wires, plugs, cap, rotor. I attempted changing the timing chain - thinking that was wore, but electronic ignition should help itself. Also, changing a timing chain on a 3.8 is like having an abortion with a coat hanger. Different fuel, plenty of cans of injection cleaner through it. nothing. I was going to change the fuel filter again, but that wouldn't explain the eradic idle either. I somehow think the idle and stall are linked. Some mornings, i'll start the 3.8 and the engine will just start racing. I'll shut it off for a few seconds, start it and it starts fine? crazy stuff.

I might give the tps a try on my 5.0. I just was hoping there was someone who had that same lope in their throttle i had in both my cars. Thanks!

 

[dwinthrup]

my truck dose have the boggy delay on take off too but that a 98 s-10 and the check engine light says it's the crank position sensor