pulled codes, please help

[BowTie Eater 5 Liter]

just pulled codes and this is what i came up with

32- evp circuit below min voltage of .24
67- neutral safety circuit failure
29- vss code(got the new gear to go in this week)
56- maf above max voltage of 4.5/TOT sensor output greater than self test max value of 4.8v.

can you help me fix these??? or tell me what else to check?

thanks!

[84LX89GT]

god i hate EVP sensors, had constant problems with EVP signal in the 89 GT i had only to find out there was high resistance in the signal wire from the connector to the pcm somewhere hidden far away.
-the EVP sensor, or E.G.R. valve position sensor is a sensor with a plunger than mounts to the egr valve and sends varying voltage depending on the position of the egr valve. Chances are you have a bad EVP sensor or faulty wiring make sure there's no corrosion in the connector.

67 neutral circuit failure - don't worry about it especially with an engine swap unless you feel like doing more wiring if it's not already installed.

29 see what happens with new gear, you may have a bad vss sensor or wiring

56 either the mass air flow sensor is faulty or you have a wiring problem. It sounds like either the MAF sensor is bad or there's a wire shorted to power or miswired.

[Hozer 88GTConv]

I'd get an EGR simulator plug from ebay. Some guy in Colorado sells them. All it is is a male plug that fits into the egr plunger harness and sends a 2.2vdc signal. That will eliminate the egr code.

The MAF code means you need to check the signal wire from the MAF itself AFTER you clean the element with evaporating electronic parts cleaner.
If a cleaning doesn't work, then check the signal voltage on the appropriate wire (Tan/Light Blue wire 18 gauge is the signal return, dark blue/orange is the signal wire)
Or go to a junkyard and get a MAF sensor from any FORD from the right period, I paid $5 for a couple of 'em. (at the parts store new, they were $200!!)

A bad VSS will hurt your drivability off of the gas, as the car returns to idle off the gas it may hang up or hunt/surge...take the sensor off and check voltages or swap (they are cheap!)

good luck...

[Joel5.0]

To confirm a bad MAF due to code 56, disconnect MAF, start engine and let it idle for 3-5 minutes, shutdown and rerun a KOEO self-test. If code 66 shows up, the MAF is kaput....if it doesn't....wiring problem tracing time...This is the code that is causing the problems you've been having @WOT...LUK

[BowTie Eater 5 Liter]

Originally Posted by Joel5.0

To confirm a bad MAF due to code 56, disconnect MAF, start engine and let it idle for 3-5 minutes, shutdown and rerun a KOEO self-test. If code 66 shows up, the MAF is kaput....if it doesn't....wiring problem tracing time...This is the code that is causing the problems you've been having @WOT...LUK

thanks joel, do i need to disconnect the bat. first and restart the computer?

i really appreciate all your help throughout all my problems, cheers bro!

[Joel5.0]

Originally Posted by BowTie Eater 5 Liter

thanks joel, do i need to disconnect the bat. first and restart the computer?

i really appreciate all your help throughout all my problems, cheers bro!

Nope....the fact that code 66 shows up (if it does) would be considered "enough data" to id it as the failing sensor. LUK how the test goes. GL

[BowTie Eater 5 Liter]

one more Q, havnt got around to pulling the mass air plug yet, going to this afternoon, but ive got a 95 5.0, will that mass air sensor work in the 91 if the mass air is the culprit? if the sensor is wrecked, i will replace it asap, but i need to drive the car until the new one would be in...

[Joel5.0]

You can try it out, they are different sampling tube styles, but as long as the connectors are the same style....I would try it, besides you already have it available. LUK

[BowTie Eater 5 Liter]

just pulled codes again, and 66 did show up. i would really like to know if the mass air sensor(going to just swap the sensors, not the actual tubes, ive got the 73mm c&l in the 91, just the stock crap in the 95) from the 94/95 motor will work the same, it looks the same, connector is the same, for the 5 min it takes to switch them, ill do it.

[BowTie Eater 5 Liter]

oh, should i reset the computer when i switch over sensors??? and the car was in gear when i did the koeo test, would that affect the neutral safety circuit???

[Joel5.0]

Originally Posted by BowTie Eater 5 Liter

oh, should i reset the computer when i switch over sensors??? and the car was in gear when i did the koeo test, would that affect the neutral safety circuit???

Yup...new sensor, new memory. If you were running the KOEO self-test with the tranny in gear....there's a a reason for the code 67 to show up. LUK how the replacement '95 MAF does.

[BowTie Eater 5 Liter]

well, the 95 sensor is in, driveability seems a lot better, but the check engine light still comes on during wot, going to bump up fp some more to see if it will cause the check light to stay off, ive got my injectors coming this week so hopefully lack of fuel is my problem....

[BowTie Eater 5 Liter]

well pulled code again after 2 days of driving with the 95 sensor in, im getting codes 29, 32 and 56(again???) anyone have any other ideas?

[BowTie Eater 5 Liter]

oh, would i be better off driving with the mass air disconnected for the time being until i figure out wtf is wrong?

[Joel5.0]

Mr. code 56....., two MAF having the same problem.....reads as if the tube has something to with it, MAF going way past its signal voltage boundaries = airflow restriction under operation (WOT in your case, or MAF > 4.5vdc)......umh....what type of ECM are you using BTW?....if driveability is ± OK, leave MAF connected. LUK

[BowTie Eater 5 Liter]

ecm? its all stock computer and whatnot, ive got a 30lb sample tube(will have the 30lb injectors this week to match) for the c&l. i dont think the mass air is actually wrecked, should i try the stock meter and see what it does??? i know its too small for the motor, but do you think its worth a shot?

[BowTie Eater 5 Liter]

well swapped back in the stock mass air METER to see if she runs any differently, hopefully it will run better, but who knows

[vristang]

This may be a dumb question at this point, as I am coming in at the halfway point.
Have you cleaned the MAF sensor?
Some say to use Q-tips and a solvent (usually Windex or Alc), but I prefer to spray the 2 wires with brake cleaner. Brake cleaner will not leave a residue behind, unlike most solvents, plus the wires are fairly sensitive to stretching (resistance changes), so I have no desire to touch them with anything.

C&L should be able to tell you if the 2 sensors you are using are the same/interchangeable.

Good Luck,
jason

[BowTie Eater 5 Liter]

allready done that