quiggs12

I posted a little while back that my TPS seemed bad and it was. I bought a new one and installed it. It is adjusted correctly and my timing is dead on! It starts and idles normal but can't accelerate. The air flow meter seems to make a loud noise when it gets under heavy load. I am NOT able to drive it up-hill at all! There are NO codes. My ECU seems to be working properly (I had codes before the TPS install but erased them). I have continuity between the TPS and ECU. What should I check? My truck is an 88 with an 87 22R-E in it and I think it hates me... Plugs and air filter are new too. Thoughts??? Thanks

sam333

Have you checked your fuel pressure? Have tried running it with your TPS unplugged? Have you tested your AFM?

quiggs12

Fuel supply is good. Same issue when TPS is unplugged. I have not tested the AFM yet.

sam333

Have you checked your fuel pressure? You said "fuel supply".There can be enough fuel to idle and even run poorly but not enough to run under load. If you have not allready , do a pressure test ( under load is best) and a volume test. When and how did this start?
Hows your cat?

quiggs12

I have NOT done an actual gauge test. But when I installed a new fuel filter I turned the fuel pump on with the connection hose into a bucket and the fuel had plenty of pressure...

Cat is a couple of years old. P.O. replaced the exhaust from the Cat back.

sam333

Just went back and read your other threads , you gatta whole can of worms there.

quiggs12

THANKS!

2 weeks ago it ran pretty good! But being an idiot-perfectionist I wanted to tweak it more... and here I am.

When I initially rev the engine there is a loud (almost like a backfire somewhere in the air supply hose or air flow box... It is hard to pin-point it. Somewhere along the way it sounds like I have some sort of exhaust leak around the header (sounds like a helicopter). I am not sure if that was there before my can of worms or not...

quiggs12

The exhaust leak is likely the cause of the jumping the motor was doing when it was in the wrong timing position.

Smeddy2

If I were you, I'd check the AFM to make sure it checks out electronically too. I had a problem like that once and I tweaked my TPS and all that and still had a problem accelerating. Stupidly enough, my idiot self switched the number two and number three spark plug wires. Make sure everything is plugged in right and you're firing on all 4.

quiggs12

That's funny... But yeah my plugs wires are located properly. The funny thing is 2 weeks ago it ran without issue (major issue anyway). Then the TPS went and now maybe the AFM. I am planning on looking at it tonight. I am wondering if the fact that the engine sat for a little while with the P.O. and I have run seafoam in it a couple of times if I gunked up the AFM sensor from all the crap in the throttlebody??? The only thing I know for sure is my truck is like a child, no matter how much love I have for it, it still hates me!

Smeddy2

well anything knocked loose from seafoam wouldn't make it back to the AFM. If you didn't take off your throttle body when you replaced the TPS, it may be a good idea to take off the throttle body and give it a good scrub! Make sure you don't get your new TPS wet with anything. Probably isn't what your issue is but its still a good idea. They get nasty. Is your throttle cable such that you have just a little bit of slack in it?

quiggs12

There is a white residue that seems to be left over from the seafoam that has made its way around the AFM... I was assuming it was from backfiring but honestly I have no clue (just guessing). Hence, why I am here.

Smeddy2

The AFM is the flap that measures air coming in by the air filter. There should be no backwards flow to that part. Backfire is something you get when you are running too rich of a fuel/air mixture and the leftover gas doesn't burn up in the cylinder and it ignites when it hits the exhaust system. So the boom you hear is a tiny explosion of left over gas in your exhaust.

quiggs12

I agree but where do you think the residue is coming from?

Smeddy2

I have no clue unless there is something getting by the air filter. Regardless, if there is residue on your AFM...then I'd say you definitely need to check it to make sure it is functioning properly.

quiggs12

Air filter is new so there shouldn't be a problem there... I checked the diagrams to ensure all my emissions and vacuum lines were in the correct places and can't find an issue there. hmmm???

Smeddy2

Is it a manual transmission? How old is your clutch and flywheel? Could be a clutch slipping. How about your fuel injectors, have you tested those? Pull a spark plug and see what they look like, it will tell you if your running lean or rich. If it sat for a while, maybe your fuel pump is bad. The gas tank can get really rusty and clog up a fuel pump and it could clog up your new fuel filter again if it isn't fixed. Fuel pressure regulator could be bad. Sometimes a bad O2 sensor can cause poor acceleration. Thats all I can think of for now.

quiggs12

Manual Transmission. It ran fairly well about 2 weeks ago... It is NOT the clutch. It has new gas and a new filter. Pump has been tested and is fine. Fuel pressure reg. maybe... O2 sensor is unlikely because there is no code.

Smeddy2

Well there are a few causes to no acceleration:

EFI Issues
Timing Issues
Transmission issues

Most of these can be either mechanical or electrical malfunctions. Looking at the spark plugs can tell you if its a fuel/air ratio problem. You say you have the right timing and you say you don't have a slipping clutch. That means you need to turn your attention to all the little systems that mess with air or fuel mixture. If it had been sitting for a while, my guess would lean towards the fuel side of things. Old gas wreaks havoc on EFI components. Take a look at those spark plugs and tell us what you see. Those can help a lot in finding out what to look at.