Going to part her out if I cant figure this out

[able8]

Ok, been scanning and reading the post now for a week or so trying to find the solution to my problem.

93xlt 302

brand new : Fuel Filter, spark plugs/wires, dist. cap and rotor, fuel pressure regulator, tps, throttle body gasket, IAC Cleaned the mess out of the TB. gone over every inch of vacuum lines and found one that was disconected (controlled the air con selector switch,"def/floor/vent") umm coolant level is good to go, new cat new exhaust, and a over priced fuel injector and rail cleaning done by a "pro" b/c i didnt feel like taking off my intake mani.

Problem: surge idle and almost dies when you lean on the throttle. if you go wide open throttle it just bogs down and rpms drop and back fires a little (like little pops) but when you let off of full throttle it revs back up to about 1500 rpms for a sec and then down back to the normal 800-900ish you can rev the motor little by little to get the rpms up and keep them up that is how i am currently driving it back and forth. now here is the fun part it doesnt trip the light. so when i tried the little wire trick i got nothing, and yes the light comes on when you start it so the light is functioning. went to napa and schucks auto tried both of there scan tools and wouldn't you know it no codes...the only thing I can think of is MAP and or distributor or maybe timing.

 

[miesk5]

yo!

I see you have done a lot of the basic checks & following tips by Ryan (Fireguiy50) already + cking for vacuum leaks - good job!!!

try this;; Self Test - NO CODES Troubleshooting

http://fordfuelinjection.com/index.php?p=44

Think you can iggie a lot of the EEC connector tests for now...may do more harm than good

+ another tip by pur pal BroncoJoe; ck coolant level too

Also, how did da Plugs look? were they fouled by Fuel deposits?

Also, when you did da KOER portion of Self test, was engine warmed up to Normal Operating Temp?

a few guesses;

Operational Description, pic & Parameters (click on Sensors; MAP sensors are only used in Speed Density systems (83-95)

Source: by Ryan M (Fireguy50) at fordfuelinjection.com

MAP SENSOR Overview, Testing, Symptoms & Causes; "... Surging, Rough idle, rich fuel condition, which may cause spark plug fouling, Detonation due to too much spark advance and a lean fuel ratio, loss of power and/or fuel economy due to ******** timing and an excessively rich fuel ratio, vacuum leak will reduce intake vacuum and cause the MAP sensor to indicate a higher than normal load on the engine. The computer will try to compensate by richening the fuel mixture and retarding timing -- which hurts fuel economy, performance and emissions

Source: by aa1car.com

Testing w/DVOM & Overview :...The most accurate way to test this sensor is to measure output using a DVOM (digital volt-ohm meter). In this case the meter must have a frequency measuring ability..."

Source: by kemparts.com

ECT (Engine Coolant Temp) - but that would give ya a Code & CEL unless eng was Not at norm op temp as cited by Ryan; "...To test an ECT sensor you will need a volt meter. You can test the ECT by back probing the harness while reading the voltage returning to the EEC. Or you can removing the connector completely and test the resistance between the 2 pins on the ECT. The engine temperature must be greater than 50�F (10�C) to pass the KOEO Self-Test and greater than 180�F (82�C) to pass the KOER Self-Test. To accomplish this, the engine should be at normal operating temperature..."

Do you have a vacuum gauge? My 96's vac line look good until I do somethAng like ck tranny filter, then when I push dip stick back-in, I cracked a Nylon vac line to da throttle body...

Ck timing

 

[able8]

ok so upon further examination and studying my chiltons on the throne i realized that the previous owner had the spark plug wires done wrong. he or she had it wired like a 94 302 and according to my chiltons it has a fireing order for 1993 and older and one for 1994 and newer...ok my bad for not really checking what I was doing and just replaced the wires one by one instead of looking into the fireing order...now the truck runs just like it should if the timing was off real bad...

 

[shift1313]

so is it running fine now? or do you still have some issues?

 

[able8]

ok so still have issues but like i said it is running like the timing is all off..but until i get the codes i am at a dead loss

 

[able8]

ok pulled codes

KOEO:

327,637

KOER:

167, 225,129 so looking at the codes, i am thinking the transmission oil temp sensor is robbing voltage from the other sensors?

327 EGR Valve Position (EVP)

sensor, Pressure Feedback

EGR (PFE) sensor or EGR

Pressure Transducer (EPT)

 

[BroncoJoe19]

Oh no, with all those voltage issues, I'd suspect poor connections and poor grounds.

Check your battery connections, but also the little ground connections on both sides of the radiator support and the one near the PCM.

To check the connections, often if one simply pulls them apart, sprays them with electronic contact cleaner and then puts them back on with a little dielectric grease that is all that is needed.

 

[able8]

Any chance all the listed sensors are on the same wiring umm harness or what

 

[Johnny Reb]

Any chance all the listed sensors are on the same wiring umm harness or what

I have found -to be the biggest BAD CONNECTION -IN ELECTRICAL WIRES--------is where the wireing harness goes through the firewall. It seems with all the spray the auto companys spray around it to keep dirt and moisture out. In time after heat-the spray goes down in between the harness and causes a mess. What I will do is take a cleaner or gas(and I DO NOT EVEN TURN THE SWITCH ON---UN-HOOK YOUR BATTERY FOR SAFETY) AND CLEAN THE HARNESS -ENDS OUT REAL GOOD AND AFTER ABOUT 24 HOURS-----WHEN IT IS GOOD AND DRY---I PLUG IT BACK TOGETHER. jUST Like you would do takeing a distributor out-MAKE SURE THE BATTERY IS UNHOOKED-----IF YOU HAVE EVER CRANKED OVER A ENGINE AND PUMPED THE GAS PEDAL------WHAT YOU HAVE JUST DONE WAS CREATE -A HAZZARD------IF YOU DO NOT UNHOOK THE BATTERY-----AS YOU PULL THE DISTRIBUTOR OUT--IT CAN EXPLODE ----I FOUND OUT THE HARD WAY AND ABOUT LOST MY EYE SIGHT. I saw a little spark and next a big spark and BOOM-VERY DANGEREOUS-SO PLEASE ,FOR YOUR OWN SAFETY ---ASK SOMEONE WITH EXPERIENCE AND USE ALL SAFETY PRECAUTIONS.

 

[BroncoJoe19]

They all go to the PCM, therefore it is important to check the grounds.

 

[miesk5]

yo!

MFer! I had my reply ready to go & another window froze and lost it all!

here is a re-cap

Concentrate on da EGR Code first; 327 EGR Valve Position (EVP) sensor, Pressure Feedback EGR (PFE) sensor or EGR Pressure Transducer (EPT)

 

[lascassas_camper]

Sounds like your timing is off, the distributor, coil, or timing set is suspect to me (ie: the little pops coming from the tailpipe/backfiring) this is classic electrical.