engine problems

[albrosm]

Well i hopped in the x today and took off down the road and the engine will surge, like it stall for a second and then its ok, got home and ran the koeo and the koer and this is what i got 112,122,157. it only seems to happen when the eng is warm and when i start to accel. anyone with some ideas of what it might be

 

[MrShorty]

My suggestion: Identify which codes are KOEO codes, which are KOER codes, and which are continuous memory (CM -- after separator pulse of KOEO test) codes. Then focus your attention on the KOEO codes, as they almost have to be electrical in nature.

Note that a KOEO 112 is often triggered by a cold engine. Make sure to perform the test son a previously warmed up engine.

 

[albrosm]

it also seems to lack power too, and believe the codes came from the koeo.

 

[albrosm]

i've check on alot of other post and it seems to lean toward the fpr or the iac or even the coil pack, but any how hate to change anything that does not need to be.

 

[albrosm]

well i tried to check codes again first i disconnected the battery for about 1 hr then i took it for a drive and it did it again it sound like a loud humm this it surgers and bucks, did the koeo got code 122 tps below min voltage, and did the koer did not any codes, so i check the tps as in the haynes manual says to seem to ok i also check and cleaned the maf and the iac too but still has the problem, so what now any help

 

[MrShorty]

Was it a KOEO 122 (before separator pulse) or a CM 122 (after separator pulse) or both?

Note that there is more to the TPS circuit than just the TPS itself. There are wires between the computer and the TPS that could also be bad.

 

[albrosm]

it was the koeo one

 

[MrShorty]

KOEO codes almost have to be electrical in nature, because they are set with the engine off. You say that the TPS itself checks out (assuming the procedure in Haynes is adequate), so the problem is likely in the wiring between the computer and the TPS.

1) Check for Vref (+5V) at the TPS. Vref is a constant reference voltage supplied by the computer to several sensors. If you don't have a wiring diagram, I would suggest you get one. Make sure it is a wiring diagram specific to your '93, and not a "generic" or "typical" wiring diagram like Haynes often likes to use.

2) Check the return wires between the TPS and the computer. Make sure they are intact. Measure the return signal voltage to see what the computer is seeing.

 

[albrosm]

well i check the wires on the tps to the computer, all seem good. so i put a new tps on anyhow. well it still has the same problem, it surges and i hear like a hum or a buzz in the engine area just before it surges, but it only seems to do it when its warmed up, should i check the fpr i dont think you will get any codes if it going bad, or would a cat be plug up do it.

 

[MrShorty]

Did changing the TPs clear up the 122?

Wouldn't hurt to check the FPR. The computer doesn't monitor the fuel pressure, so you won't ever get any codes directly related to incorrect fuel pressure. Sometimes incorrect fuel pressure will trigger O2 sensor or MAF or fuel trim type codes. Easy enough to test with a fuel pressure gauge. However, FPr would have nothing to do with a KOEO 122 TPS code.

A plugged cat is usually more consistent that this. Basic first test for a plugged cat would be to hook up a vacuum gauge and see what the engine vacuum is doing.

Until you get pass codes from all three parts of the EEC-IV tests, I would still work on the computer codes you are getting before the other things, though.

 

[albrosm]

well today i found the problem, i started to check the wiring out again for the tps and i found a connector that was not seated all the was so i push it back together and the lock would not stay lock so i push it together and then taped it no more surging,