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Popping upon acceleration issue.

Mo Imzi

New Member
Good morning y'all. My 92 GT has been popping every time I accelerate and I cannot figure out why. I got the car straight piped and then the issue started. It also pops more at lower RPM and lessens a lot near higher RPM. Furthermore, if I gently accelerate, it barely pops at all. I think that it might be the hose from the smog system that attaches to the H pipe. It was cut when we removed the cats and now it just hangs. Do y'all think this is the issue or something else?
 

Mo Imzi

New Member
Dang man. Ny car is now hesitating every-time I accelerate it too hard. We’re thinking it’s the fuel injectors. It seems like it still has the stock 19lb injectors. I don’t think my exhaust leak would cause it to lug that much.
 

broncojunkie

Well-Known Member
As far as I know the tank is original.
It really wouldn't hurt to take a look inside it. If you have access to a scope, that would be fairly easy I think. It's not too hard to drop the tank, though. They tend to get dirt and rust buildup and that will clog the strainer attached to the pickup tube. It doesn't sound 100% like your issue, but the early symptoms are a little vague. As it gets worse, it becomes more apparent. Checking it costs nothing but time and some cussing lol. Spray some penetrating fluid on the strap bolts and all around each end of the filler neck...particularly where it enters the tank.
 

broncojunkie

Well-Known Member
My 88gt was popping through the intake and it turned out to be the tps. They're easy to check. Get a couple safety pins and pierce the wires. Use alligator clips with your multimeter. I forget which 2 wires you need to probe, but there are videos online. As you move the throttle, the voltage should change smoothly throughout the range. If the voltage bounces around or has dead spots, it's bad.
 

Mo Imzi

New Member
It really wouldn't hurt to take a look inside it. If you have access to a scope, that would be fairly easy I think. It's not too hard to drop the tank, though. They tend to get dirt and rust buildup and that will clog the strainer attached to the pickup tube. It doesn't sound 100% like your issue, but the early symptoms are a little vague. As it gets worse, it becomes more apparent. Checking it costs nothing but time and some cussing lol. Spray some penetrating fluid on the strap bolts and all around each end of the filler neck...particularly where it enters the tank.
Wow I didn’t know that could happen. It seems like the popping is timed. Like it follows a pattern. And everytime I try to step on it, it just hesitates and lugs. I might try a fuel cleaner to clean up the lines.
 

Mo Imzi

New Member
My 88gt was popping through the intake and it turned out to be the tps. They're easy to check. Get a couple safety pins and pierce the wires. Use alligator clips with your multimeter. I forget which 2 wires you need to probe, but there are videos online. As you move the throttle, the voltage should change smoothly throughout the range. If the voltage bounces around or has dead spots, it's bad.
We were able to bring the range to .98 which I believe is in the correct range, do you think it could still be the cause despite that?
 

broncojunkie

Well-Known Member
We were able to bring the range to .98 which I believe is in the correct range, do you think it could still be the cause despite that?
The range isn't the only issue you need to look for. You should be able to watch the voltage change throughout the movement of the throttle from closed to all the way open. Basically, you hook up the volt meter and slowly open the throttle while watching the meter. You should see the voltage smoothly transition throughout the entire range of the throttle position.
 

Mo Imzi

New Member
I never thought of that being an issue, thanks! Do you think something like that could be contributing to the car lugging that much?
 

broncojunkie

Well-Known Member
My lugging issue was due to a dirty maf sensor. I cleaned it with a can of maf cleaner and it was 100% better.

The popping issue came later, when my buddy owned the car. This was last year. We found the faulty tps and just replaced it. Been fine ever since.
 

Blueknights75

Active Member
If you do replace make sure to get a Motorcraft TPS sensor…Either Autozone or Advanced auto still has them. I went through hell with the BBK ones and after the third bad one someone told me to only use Motorcraft parts for electrical parts. I have been following that advice and never had any more issues.
 
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