Tiny22

I started my truck today, let it warm up, and pulled the TPS plug. Nothing happened, so after placing the jumper in the diagnosis box, i jumped IDL and E2 in the TPS plug. The idle then dropped significantly, making me suspect something is wrong with the TPS. I proceeded to take off the throttle body and plan on cleaning it. I tried testing the ohms on the TPS but it seemed a little confusing, ive never had to do that before. It seems to me the TPS wasnt telling the ECU to go into the low idle loop, does this mean the TPS is broken? Ill keep trying to working on it with all of my free time (as i have been lol) The info you guys have been giving me is invalueable its helped me a ton. I am still going to check the other sensors too. Hey 88toy4wd, i hope all of my problems help you solve yours!

Co_94_PU

iTrader: (-1)

Explain what you did and what you found confusing and someone might be able to clear it up. Doesn't help the manual has decimals misplaced either

Basicly somewhere in the .9 to .6mm range it needs to register that the throttle is closed. Specificly it says 0.57 and 0.85, google translates these to 0.0224(22.4 thousandths) and 0.0334(33.4 thousandths). With the switch closed (0.57mm) You should have a reading between 0-2300 Ohms, with the switch open (0.87mm) You should read Infinate or no Conductivity. If you get the proper readings make sure the connections are clean bright and shiney.

Broken dirty or misadjusted are all likely. They don't like dirt and like dirty water even less.

Another helpful tip on the distributer placement, If the bolt isn't near the middle of the adjustment cut out. It's likely inserted incorrectly. (Thanks Terry, or whoevers post I saw linked in your build threads). Its a quick simple check and easy to overlook!


FYI it only takes ten seconds to clear the codes not ten minutes. And yeah it's probably not learned behavior if it happens after its been reset. But could still be bad map, I'd expect it to be something else however.

Tiny22

Ok i was able to test the TPS, and it checked out fine. What Co_94_Pu posted was helpful, i also found some info on another site that went step by step. But im still feeling like something is wrong with it. Yes i readjusted it to specs. Same problems. By now im having a wee bit of a headache

Tiny22

Mass air flow checked out good too!

Co_94_PU

iTrader: (-1)

You've tested both the TPS and AFm over the whole open to closed ranges and they don't how any dead spots correct, eg nice smooth arcs?

Have you checked the valve adjustments? If you've done it cold. Don't forget to do it again with the engine warmed up, it will change due to heat expansion.

If the cam/valve timing is correct, the ignition/spark timing is correct, and the valves are properly adjusted.. The only thing left is a leak at the valve to head junction. Do a compression leak down test, and/or get eyes on the intake valves.

Something like the water injection or seafoam type treatments will clean up any minor blockages keeping the valve from seating. If it's not an obvious blockage it could still be leaking thru rough spots, or a warped valve. In which case they'll need at the least polished.

Tiny22

Ok so i said the tps tested out fine, there were no dead spots and everything looked just peachy. After cleaning throttle body , and putting it back on it did the same things. The idle was very high and even if you jumped TE1 and E1, nothing would change. Also, if the motor was running and the tps were unplugged and plugged back in, the idle stayed the same (around 2000 rpms). I was still convinced something was wrong with it. My uncle had a 3-vze just sitting around so i popped the tps off and swapped it with mine. That made a WORLD OF DIFFERENCE!!! So im going to order a new one, maybe off of ebay, and get the idle set right, and try to get the timing corrected.

Tiny22

Ok, so decided to dig up this old post to help anyone else having the same troubles. Even the new TPS did not totally resolve my problem. After getting a bit flustered I took the truck to a local mechanic (which I hate doing) and he found that the fuel pump was weak and the tank rusty. After replacing them it still ran HORRIBLE. it misfired and barely idled until it got warmed up. All sensor values were checking out fine, so it wasnt a wiring or computer issue. He found that cylinder 2 was dead and cylinder 3 partially dead but had spark. The problem was in the fuel injectors, they had gotten clogged. After repairing, the engine runs like a top!