Quote from nossmatt "stop throwing money at it, and find the culprit." I agree with you 100% matt, but money is not an issue here, this little 5.0 has done went and got personal with me and 3 of my close friends! Here`s the low down, myself and 3 other friends share a shop that is fully equipped to build or fabricate just about anything a 40 year old boy could want, and I say that humbley and not boastfully. What tools or electronics we dont have on hand we can borrow, humbly. We have studyed the Ford shop manuels and gurue books until we are all crosseyed. we have checked fuel pressure from idle to wot, in park and on the road and its perfect. We have checked the vacuume, with a gauge and its perfect. It has all new grounds, eng to body, eng to frame, body to frame. We have checked the timing with the spout in and out. With the spout out, you can crank it and it will start retarding the timeing off of idle, and with the spout in it will turn to around 2800 then it starts retarding and when it gets to 3400, it`s backfireing through the exhaust and the timing has gone back to zero. 
...Thanks D.J....I welcome any opinions or advice that anyone might have.......
Got a 93 5.0 that will not turn up!
- Thread starter cullman
- Start date
Black1987Stang
Active Member
nosmatt
Founding Member
cullman,
tryin to figger this one out........ now understand im not flaming here.......
not possible for the eec to remove timing with no spout, it is an open circut, and thats that. if the timing is retarding, well then it has to be mechanical....which makes little sense. have you ever swapped a distributor in? there is a pickup in there that does go bad, and is hella hard to diagnose..... it reared its ugly head on me once, broke 3 bassani cats, they warranted two, and said i was on my own.......... went thru 3 tfi modules, and a coil etc..... pissed me off! found it, problem solved. try that one.......
please splain "it went back to zero" to me....... im not sure how you know this.
backfiring thu the exhuast, either hella retarded timing, or a rocker adjusted too tight holding an ex valve open...... of course, having the fuel injector harness on wrong will cause the injectors to fire at the wrong time, and can cause an ex backfire...
are you 100% CERTAIN it is NOT mechanical in nature????? I am not trying to doubt your expertise here, but if you can rule that out, you can be certain of the electrical aspect........
more thoughts,
does this problem happen in nuetral, just revving, and at 2800 it turns to ****, or is it only under load?
have you ever swapped the eec?
if you have a car with a known good eec to swap just for a test, it may save you alot of time.....
yet another thought...... the "salt and papper shakers" have those been disconnected, and cleaned, regreased, and put back together? ford actually had a campaign on these bad boys....and MANY intermittant problems are solved by cleaning these........
tryin to figger this one out........ now understand im not flaming here.......
not possible for the eec to remove timing with no spout, it is an open circut, and thats that. if the timing is retarding, well then it has to be mechanical....which makes little sense. have you ever swapped a distributor in? there is a pickup in there that does go bad, and is hella hard to diagnose..... it reared its ugly head on me once, broke 3 bassani cats, they warranted two, and said i was on my own.......... went thru 3 tfi modules, and a coil etc..... pissed me off! found it, problem solved. try that one.......
please splain "it went back to zero" to me....... im not sure how you know this.
backfiring thu the exhuast, either hella retarded timing, or a rocker adjusted too tight holding an ex valve open...... of course, having the fuel injector harness on wrong will cause the injectors to fire at the wrong time, and can cause an ex backfire...
are you 100% CERTAIN it is NOT mechanical in nature????? I am not trying to doubt your expertise here, but if you can rule that out, you can be certain of the electrical aspect........
more thoughts,
does this problem happen in nuetral, just revving, and at 2800 it turns to ****, or is it only under load?
have you ever swapped the eec?
if you have a car with a known good eec to swap just for a test, it may save you alot of time.....
yet another thought...... the "salt and papper shakers" have those been disconnected, and cleaned, regreased, and put back together? ford actually had a campaign on these bad boys....and MANY intermittant problems are solved by cleaning these........
Dont worry about flaming me, Im thick skinned! Flame away! This car may go up in flames soon if I don't figure this out.
I agree about the computer pulling timing out with the spout unpluged. When we had it hooked up to a breakout box you have the option to running on computer timing or distributor timing. Didn't seem to run any different on either. By the way, we didn't have any crazy voltages or shorts to ground.
Yes, this problem happens when reving in netural. I have watched the timing with a timing light reving in netural. This is what happens....
unplugged spout.
Set base timing to 10btdc
Plugged spout back in.
idle=20btdc (750-800rpm)
2000rpm=advances to 30btdc
3000rpm=retards back to 20btdc
4000rpm=retards back to 10btdc
over4000rpm=back to 10btdc
then between 4-4500 moves to 0 and starts popping and backfiring.
I am 100% sure that the problem is not mechanical in nature as far as the engine goes...(block, heads, timing chain, etc) because I swapped engines with a friend that had a good running 5.0. He was builing a 347 and didn't need his anymore. We took the engine that was in mine and put it in his farm truck with a carb and it ran fine.
As for swapping the eec we have had 4 different computers in the vehicle and also took my computer and put it in another car and it ran fine.
I haven't cleaned the salt and pepper shakers but I have unplugged them and replugged them at least a dozen times.
Thanks for any help you can offer.
I agree about the computer pulling timing out with the spout unpluged. When we had it hooked up to a breakout box you have the option to running on computer timing or distributor timing. Didn't seem to run any different on either. By the way, we didn't have any crazy voltages or shorts to ground.
Yes, this problem happens when reving in netural. I have watched the timing with a timing light reving in netural. This is what happens....
unplugged spout.
Set base timing to 10btdc
Plugged spout back in.
idle=20btdc (750-800rpm)
2000rpm=advances to 30btdc
3000rpm=retards back to 20btdc
4000rpm=retards back to 10btdc
over4000rpm=back to 10btdc
then between 4-4500 moves to 0 and starts popping and backfiring.
I am 100% sure that the problem is not mechanical in nature as far as the engine goes...(block, heads, timing chain, etc) because I swapped engines with a friend that had a good running 5.0. He was builing a 347 and didn't need his anymore. We took the engine that was in mine and put it in his farm truck with a carb and it ran fine.
As for swapping the eec we have had 4 different computers in the vehicle and also took my computer and put it in another car and it ran fine.
I haven't cleaned the salt and pepper shakers but I have unplugged them and replugged them at least a dozen times.
Thanks for any help you can offer.
silverstripes
Member
Have you checked for blockage in exhaust? Cats? I have seen that happen more than once. Since you didn't say whether the exhaust was changed with each motor, I am assuming it's the same.
Aliate X
Member
I HAD THE SAME PROBLEM AND FIXED IT!
If you are talking about the same problem like no matter how warm the car was, if you started it up, sometimes a long cranking time, it would run and then you nailed it and it would just rev slow and go nowehre, then start back firing into the intake and crap. It was horrible, changed all the usual stuff.
Changed the fuel pump, and no more problems, runs awesome now.
If you are talking about the same problem like no matter how warm the car was, if you started it up, sometimes a long cranking time, it would run and then you nailed it and it would just rev slow and go nowehre, then start back firing into the intake and crap. It was horrible, changed all the usual stuff.
Changed the fuel pump, and no more problems, runs awesome now.
Aliate X
Member
Lol btw wtf are the "salt and pepper shakers"? the 2 big ass plugs on the back of the intake manifold?
I had this same problem after i installed my supercharger,got every thing back together set the timing jumped in the car to try it out and it would only reach 3000rpms and cut out i was so aggrevated it was about 2.00am so i called it a night emptied my pockets to go to bed and found the spout connector in my pocket i had forgotten to put it back in,went back out and put it back in and it fixed it.
blown93feature
New Member
This may be a far stretch but have you considerd something in the fuel tank. The car will idle and even allow rpm increase until there is a high enough demand for fuel and then it's over the gremlin appears.
Aliate X, blown93feature, I did think about trash in the tank and the fuel pump.
What I did was borrow an external pump from a friend plumbed it up to a 5 gal gas can and bypassed the intank pump. No improvement. Also blocked off the return line and bumped the fuel pressure up to 100# and no change other than more black smoke out the exhaust when it starts popping and backfiring.
Good ideas though.. Keep them coming.
something is retarding the timing as the revs come up. Just cant fiqure out what.
What I did was borrow an external pump from a friend plumbed it up to a 5 gal gas can and bypassed the intank pump. No improvement. Also blocked off the return line and bumped the fuel pressure up to 100# and no change other than more black smoke out the exhaust when it starts popping and backfiring.
Good ideas though.. Keep them coming.
something is retarding the timing as the revs come up. Just cant fiqure out what.
Zero_chance
Founding Member
SOrry if you already went over this, I skipped to the last page without re reading all the old posts... but have you tried swapping in a known good PCM?
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