'93 Thunderbird fuel problem

[rodnocker1]

My '93 T-Bird (3.8L Automatic) started losing a little power on acceleration awhile back (can't say how many miles ago since the odometer broke about 6 years ago at 103,500). Here in the past month or so, it has gotten to where if I press down on the accelerator more than about 1/2", it acts like the fuel pump is losing power and the car slows down. If I ease in on the gas, it will gradually pick up speed and will run at speed limit just fine, unless I try to pass or go up an incline. Then it again starts losing power/speed.

I've had 3 different mechanics (and I mean people who are paid to turn wrenches for a living) tell me it is my fuel pump going out. I thought it could have also been my TPS or computer or any number of things yet they said "No Way, it's the fuel pump!". So I replaced the fuel pump/strainer/sender assembly and also the fuel filter.

Well, Guess What????? You got it, it still runs the same. So I am coming to my fellow ThunderChickians for some help. Has anyone else had this problem and what was wrong? Or any idea what it could be? Your input would be greatly appreciated.

Rodney

[97Bird]

Welcome to the forum rodnocker1. Another possibility is a restricted exhaust system. The cats or muffler could be breaking down and plugging the system.

[rodnocker1]

Thanks 97Bird, I had considered that also.

I had a 1974 Chevy Impala once that acted the same way but did it all at once. I took it to a Mechanic and said it acted like it had jumped time but I wasn't sure what had happened. He replaced the timing chain and gears and then found that the inside wall of the exhaust pipe (it was a dual wall pipe) had collapsed and was causing the restriction. You couldn't see it from the outside and I have no idea how he found it. I will check the muffler and Cat next.

Thanks once again.

Rodney

[rodnocker1]

Well so far, I've found out it's not the:

fuel pump
coil
TPS
muffler
Cat

I had personally thought at 1st it was the TPS because when I first crank it, it doesn't want to run and after about 10 seconds, it smooths out and idles at about 1100 RPM. When I put it in gear, it drops to 700 RPM but moving back to neutral, it jumps to 1500 RPM and then slowly eases back down to 1100 RPM. If I tap the gas pedal, it will go to 2000 RPM and hang there for 15 to 20 seconds and then slowly ease back down. Also, when I am running along in OD and let off of the gas (when the car slows enough to downshift to drive), the downshift isn't as smooth as it was before and is more of a "jar" (I don't think "solid" would be the right word to use).

When running at speed, the car feels like the power to either the fuel or spark is being dropped (again, like it is running out of gas). You can feel it "jumping" as you drive.

Also, is there anywhere I can get an inexpensive code reader for my '93? I've found them for the '96 and up for around $100.00 but they aren't for the '93 nor are they cheap (priced). My Haynes manual says to jump across a couple of contacts and use a multi-meter. then count the needle pulses.

My Wife says I need to scrap the car because of the problem I am having with it plus a little "Custom Body Work" that a deer and my Ex-Daughter-In-Law helped me with but the car is paid off, has been dependable (up until now), and gets great gas mileage. I don't see getting rid of the car due to just a little cosmetic damage and what will probably end up being just a minor problem (if I could ever figure it out).

Anyway, I'm still looking for suggestions.

[97Bird]

This is a tough one to troubleshoot without having the car in front of you, running! Using a multimeter is going to be the cheapest way to check the codes. You have to use an analog meter for this. Have you replaced the spark plugs recently? If not, I'd install a new set. Have you checked the air filter and inlets to be sure there is no restriction in the air intake components? While you have the plugs out, do a compression test. Have you checked the ignition timing? Using a socket and breaker bar on the harmonic balancer bolt, rock the engine back and forth while watching the distributor rotor to see if there is a lot of slack in the timing chain. Check all of the vacuum hoses to see if they are brittle or cracked and that they seal tightly. Let us know what you get for codes.

[Bob9646]

plug wires?

[Bob9646]

Originally Posted by rodnocker1

Also, is there anywhere I can get an inexpensive code reader for my '93? I've found them for the '96 and up for around $100.00 but they aren't for the '93 nor are they cheap (priced). My Haynes manual says to jump across a couple of contacts and use a multi-meter. then count the needle pulses.
.

Don't ever waste your money on an OBD I code reader, those things are just switches and little lights. Just follow the directions in the haynes manual, except instead of a multimeter you can use a wire with some clips and instead of counting the jumps on the multimeter just sit in the car and watch the check engine light blink.