tbone388

Hello forum :-)
You folks are great!
I have a 1993 f150 supercab 5.0 2wd automatic. What started as a no spark issue, (which is now fixed - turned out to be a poorly grounded ECM, so I replaced it) my truck has been running rough. It gets worse as the engine warms up. I had replaced the distributor, plugs, wires, ignition coil, ECM for the spark issue, then later I replaced the air filter, oil, oil filter, TPS, cleaned the VERY DIRTY throttle body and cleaned the ACH. I've visually checked the vacuum hoses, no apparent leaks there. The wires are in the correct position and I did my best to prevent cross firing. I used gas treatment, oil treatment. I replaced the "brain box" computer but was told that, that was not necessary, so I returned it. (It ran the same with the new computer) I was told by a mechanic it was the TPS. That mechanic said that codes don't really tell you anything specific. So.. by his advice, I replaced the TPS very recently and it did not fix the roughness, and even seemed to make it worse. I did not run any codes, the check engine light comes on when the engine gets warm. Could it be the EGM? Did I put the TPS in wrong? Fuel pump? I'm going crazy! HELP!! PLEASE!!

Forge-World-FORD

Pull codes.

Aktech

I don`t know what a egm is. And x2 on pulling codes.

centurion351

Could be EGR (exhaust gas recirculation). Never heard of EGM. But try to scan a code from OBD1 scanner.

tbone388

Ok, Thanks folks :-)
I had the codes run.

The only codes in the system were:
"Key on engine off keep alive code 332 - DPFE EGR system, 628 - Transmission control System"
They suggested a new EGR valve.
I replaced the EGR with little or no difference in performance.

I'm at a loss for what is causing this engine to run so poorly.
Any more suggestions?

Thank you!!!

Aktech

Code 332 in my book is insufficient flow detected. Test hose and evp. And ur trans is starting to slip. How did u pull codes? Thought before 94 where 2 digit codes.

tbone388

Had a garage pull the codes with a computer. Code 332 was the code it read. I checked the vacuum lines, a couple of them were broken. I bridged the breaks with flexible tubing.
I was thinking there maybe blockages somewhere in the parts of the old vacuum tubes. I have no idea how to check vacuum tube flow. Since the CEL went off after replacing the EGR valve, I assumed the EVP was fine. Wouldn't the CEL be on if the EVP was bad? here is what I think is the DPFE (no parts called "DPFE" show up on the parts websites for my truck) Is this the part that may need replacing? -

http://www.google.com/imgres?imgurl=...JOB_V8McnkIgDj

- that is what mine looks like. Since it's a sensor, wouldn't the computer send an error code for that or the EVP? One of the vacuum lines goes from the EGR to the part in that link.

Thanks for your input :-)

Forge-World-FORD

No.

Code 332
EGR did not open/respond during test or if memory code, did not open intermittantly – EVR or PFE.

Besides the EGR valve there is also the EGR position sensor and EGR vacuum solenoid. The solenoid might need replacing or it can be an issue with vacuum itself.

Aktech

Test the hose,evp and egr with a hand vac pump. The evp is tested with multimeter and vac pump. The evr usually never go bad. But u never know, u can test that to if u want. After that test the circuit on the evp.