Whos got skills diagnosing??

[RACER]

I wont bore with all of the details, but the car has been down now for nearly a year. Last June while driving normally the engine backfired and stumbled then quickly recovered. Happened the next day as well but never stalled out. Came back out from my errand and engine would crank no start. I thought no biggy the TFI went out...so I hoped. BTW 89 lx 5.0 5 speed 275rwhp
After being convinced the injectors were not pulsating I mistakenly moved the dist clockwise giving it way more advance and it started...that ruled out alot of things. However after swapping alot of items the engine will not start unless the dist is advanced (not drivable)
Items ive replaced or swapped with good replacements
1. PCM
2. Maf and all injectors
3. VSS
4. TPS
5. EGR
6. fuel pressure reg
7. Fuel pump
8. replaced ground strap and even added another
9. Map
10. o2 sensors
11. complete dist..
12. TFI

Cliff notes...engine will not start without manipulating the dist to about 40 degrees spout out...ive tried everything

Thought id try here first...if I cant get fixed who can recommend an ace mechanic that "will" be able to fix without charging more than the car is worth

Brian
RACER

[SmithEvo]

I wont bore with all of the details, but the car has been down now for nearly a year. Last June while driving normally the engine backfired and stumbled then quickly recovered. Happened the next day as well but never stalled out. Came back out from my errand and engine would crank no start. I thought no biggy the TFI went out...so I hoped. BTW 89 lx 5.0 5 speed 275rwhp
After being convinced the injectors were not pulsating I mistakenly moved the dist clockwise giving it way more advance and it started...that ruled out alot of things. However after swapping alot of items the engine will not start unless the dist is advanced (not drivable)
Items ive replaced or swapped with good replacements
1. PCM
2. Maf and all injectors
3. VSS
4. TPS
5. EGR
6. fuel pressure reg
7. Fuel pump
8. replaced ground strap and even added another
9. Map
10. o2 sensors
11. complete dist..
12. TFI

Cliff notes...engine will not start without manipulating the dist to about 40 degrees spout out...ive tried everything

Thought id try here first...if I cant get fixed who can recommend an ace mechanic that "will" be able to fix without charging more than the car is worth

Brian
RACER

mr2beerz

[SDK]

The timing chain got off somehow. Maybe the cam gear is loose

That would explain the backfire and why it will start if you get the timing just right it will idle but ou can not get the rpms up.

[RACER]

Is that even possible? Pretty sure thats a wives tail...isint it?

[SDK]

Does it run good at idle but then dies when you open the throttle. A stripped dist gear is more likely but you said you replaced that

[RACER]

It has a loafing idle and will stall out. At wot it sounds normal...no misses

[SDK]

I still think it's the cam shaft gear. How about smoke. What is spout out? Are you timing it with a light. How do you now it is 40 degrees advanced?

[68GTO]

You would have a camshaft/ignition timing issue if you need to advance your distributor that far for it to fire. Have you used a timing light with an advance to determine at what degree your spark is happening?

1. Set car to TDC compression stroke on #1 (or whatever the Ford uses for checking timing) - zero mark on harmonic (if that is how ford does it).
2. Hook up timing light, put lead on that plug wire
3. Turn ignition to ON and leave it
4. Set timing light advance to where your car should be timed (e.g. 10 degree BTDC)
5. While holding trigger on timing light, turn distributor until light flashes. That is where you set the distributor.

Make sure you have unplugged the distributor plug for the computer before you attempt this

[2 beer]

how many miles are on this thing? Has the engine ever been opened up?

[RACER]

Ive had the engine in/out probably 3 times since ive owned it in 7 yrs. Last compression check was 140 all cylinders. ( done diganosing this problem) Heads are take off gt40s from my cobra, gone thru 3 yrs ago. Short block is stock except cam. 115k

[2 beer]

Ive had the engine in/out probably 3 times since ive owned it in 7 yrs. Last compression check was 140 all cylinders. ( done diganosing this problem) Heads are take off gt40s from my cobra, gone thru 3 yrs ago. Short block is stock except cam. 115k

what kind of timing chain is in it?

[RACER]

stock...I know where your going with that, but has anyone actually seen a timing chain jump on a 5.0? I was under the impression it was a wives tail

[2 beer]

stock...I know where your going with that, but has anyone actually seen a timing chain jump on a 5.0? I was under the impression it was a wives tail

anything is possible with enough slack. I have seen some pretty slacked timing chains.

It is some sort of timing issue. So if like you say your distributor is all ok that really doesnt leave a whole lot. Only reason you will get a backfire out the intake is if valve timing is off.

[SDK]

anything is possible with enough slack. I have seen some pretty slacked timing chains.

It is some sort of timing issue. So if like you say your distributor is all ok that really doesnt leave a whole lot. Only reason you will get a backfire out the intake is if valve timing is off.

I told him that 12 hours ago. KTHXBYE Leaking fuel or something could do it bet he said he replaced the reg and injectors.

[minnesota_duane]

I am going to go with the masses and say cam timing is off. Chain jumped, dist roll pin sheared, computer toasted. Pull the timing cover and have a look after what you ahve been threw so far this is pretty painless and will only cost you about 15 bucks and some time.

Another thing that can give an intake backfire is a lean miss, ever see a nitrous explosion?