91 no start and no codes

[thor151]

Any help would be appreciated. I have a 91 mtx. The tach was cutting out intermittently and the car would run horrible. Once revved up it would start working again and run fine. I replaced the crank sensor and it ran good a week or so then did it again. I them replaced the cam sensor. Also drove fine about a week. Now the car won't start at all. Cranks fine and tries but won't start. Any ideas? I tried checking codes and it shows 21,24,34,85
Thanks in advance.

 

[SHOdded]

Gapping the crank sensor is a PITA, might need to check that. No water pump leaks? Any oil on the old cam sensor/connector when you replaced it? No electrical gremlins prior to or alongside? Battery/alternator/grounds/cabling checked & verified? Sometimes wires get pinched when the intake is re-installed, particularly when front-end engine work (timing, CKS, water pump etc) is being done. Any oil leaks? Checked the plugs/wires?

I'd also check the DIS, make sure it has a) heatsink grease on the back, b) a good ground (strap from intake to firewall), and c) the connectors are intact and tight-fitting. If there is any engine movement (e.g., worn motor mounts), that can put stress on the DIS.

As for the codes:
21 Engine Coolant Temperature (ECT) sensor out of range - ECT
24 Intake Air Temperature (IAT) or Vane Air Temperature (VAT) sensor out of range - IAT VAT
34 EVP - (R) EGR did not respond properly during test - EVP
EVR - (O, R, M) EVP sensor is/was high - EVR
PFE - (O, R, M) PFE sensor is/was out of range - PFE
85 2.3L T/C Automatic - 3/4-4/3 Shift solenoid - Transmissions
CANP solenoid (ALL 1989) - Solenoids
(M) 1.9L MFI - System has corrected rich condition - Fuel control

 

[thor151]

Thank you, as for the crank sensor I gapped it at .030 when I put it in. There was no water pump leaks. The cam sensor had oil residue on the outside of it... I will check for wires in the daylight tomorrow. There was light oil near the crank sensor but nothing appeared to be touching it. And I will check the DIS tomorrow as well.

 

[luigisho]

Does this car even have EGR?

 

[rubydist]

you have either a power or ground issue to some of the sensors, or a bad pcm. the iat and ect are on the same power circuit from the pcm, so whenever they are both setting codes it is almost 100% that it is a power or ground issue to that part of the circuit, or the pcm is bad.

your engine will not run worth a crap with the iat setting codes, so you need to fix that before worrying about anything else. I would be ohming out the harness from the pcm to those sensors next.

 

[thor151]

Does this car even have EGR?

Yes the car has egr but I've had that code since I got the car years ago.

 

[thor151]

you have either a power or ground issue to some of the sensors, or a bad pcm. the iat and ect are on the same power circuit from the pcm, so whenever they are both setting codes it is almost 100% that it is a power or ground issue to that part of the circuit, or the pcm is bad.

your engine will not run worth a crap with the iat setting codes, so you need to fix that before worrying about anything else. I would be ohming out the harness from the pcm to those sensors next.

Thank you. I'll see what I can find for power and ground to those sensors. I don't know how to ohm the harness but I'll see what I can find after work and look it up.