1993 Explorer fault codes, misfire and exterior questions

[Karpov]

Hi!

I have 1993 explorer 4.0ohv.

When i start "over night" cold engine, idle is pretty rough and misfiring (exhaust says tsap tsap... tsap... tsap tsap...).

Runs cold 5 cylinder? or less too but not allways. When engine warms up, it runs 6 cyl i think but idle is little bit waving and little bit missfire. On higher rpm it wont misfire.


Mpg is normal and i get these fault codes:

Engine not running:

53 Throttle Position sensor too high - TPS

66 Vane Air Flow (VAF) or Mass Air Flow (MAF) signal low - VAF MAF
Transmission Oil Temperature (TOT) signal low (possibly grounded) - Transmissions

95 Fuel pump: open, bad ground or always on - Power / Fuel Pump Possible bad fuel pump ground or open between fuel pump and pin 8 at PCM (Fuel Pump Monitor signal) - Power / Fuel Pump CircuitsCircuits


Engine warm and running:


35 EVP - Engine RPM's too low to test EGR system - EVP / EVR - EVP sensor signal is/was high - EVR / PFE - PFE sensor signal is/was high - PFE

53 Throttle Position sensor too high - TPS

85 2.3L T/C Automatic - 3/4-4/3 Shift solenoid - Transmissions

CANP solenoid (ALL 1989) - Solenoids


What i do first? (New spark motorcraft platinium plugs and wires are coming btw)






Second part:


How i can get dashboard thin panel off? (that which rounds climate control panel and rear defrost switches etc).

And how i can remove door panels? I wanna but new speakers rear and front + but lights on window-central lock panel.



Sorry bad language im not born to english speaker!

 

[MrShorty]

By '93, all EEC-IV systems that I know of were outputting three digit code rather than two digit codes. I would suggest repeating the tests to make sure you are counting the codes correctly.

 

[Karpov]

Thank you! Now right codes:


Engine off:

First was 111 but then

124
(M)
TP voltage was higher than expected - Fuel control


Engine running, after couple minutes:

538
Insufficient RPM Change During KOER Dynamic Response Test
R

538
Invalid Cylinder Balance Test Due To Throttle Movement During Test
R

538
Invalid Cylinder Balance Test Due To Cylinder Identification Sensor Circuit Failure
R


How about now?

 

[MrShorty]

The first 111 means it passed the KOEO test.

CM 124 points to a fault in the TPS circuit. TPS is a basic potentiometer, so I would suggest testing the TPS with a volt/ohm meter.

KOER 538 is almost always operator error, indicating that you neglected the "goose" test.

At this point, I would repeat the KOER test and make sure to perform the goose test when indicated, then I would probably clear CM, test drive, and see if the CM 124 comes back immediately or if it waits a while before it comes back.

 

[Karpov]

Goose test means that i have to give som revs to engine while testing or bressing brake or what?


When the test starts idle rpm was about 1200-1300rpm and then they dropped 600-700 as should be i think. Then that 538 appeared.


So how i should do it right?

 

[MrShorty]

Here in my notes on pulling EEC-IV codes thread, I explain when and how to perform the goose test as part of the KOER test protocol:
http://www.explorerforum.com/forums/showthread.php?t=147734

 

[Karpov]

Now i give wide open throttle. After rpm down's and before etc.

Nothing changes. 538 was still coming.


Car was emission test today.

Idle 2000rpm i think

CO% 0 0
CO2: 14,5 14,5
HC ppm: 0 17
02: 0,8 0,5
Lambda 1,02


Does that say anything? I dont know what kind of emission test are in usa. Inspector says these was good and clearly passed test.

 

[MrShorty]

One possible legitimate cause of KOER 538 is a problem with the TPS. Does your CM 124 come back after being cleared? Perhaps a more thorough test of the TPS is in order.

 

[Karpov]

Yea 124 come back. Can i just replace tps to new (bolt on) or adjust it?

 

[MrShorty]

If you are reasonably certain that the fault is in the TPS itself, it is fairly easy to replace (a couple of bolts/screws and an electrical connector are all that hold it on, I believe). If you are replacing as a "guess and check" diagnosis strategy, it is also relatively inexpensive. This might be one where you replace it and, if it does resolve the problem -- great. If it doesn't resolve the problem, then we can go into the more difficult task of tracking down the other possible causes of the symptoms you describe.

 

[Karpov]

I know, i just ask because aerostar repair manual says that tps must be adjust if you replace it but im not sure what engine that means...

If tps is okay, what can cause problem?


Because i have to order spare parts to usa it will take at least week or two so i must do researching job But i cant buy all spare parts what i think is going broke...