when you unpug the maf does it change the idle?
Mystery problem
It used to be random, but the car runs like crap now. It is not driveable. It sounds like it is a 6 cylinder diesel. It has no throttle response, no power and backfires like a SOB.
Here is what I have done. The issue has gotten better since doing all this work, but it is still there.
1. Both 02 sensors were replaced
2. Replaced the Mass Air Flow sensor
3. Spark plugs were replaced. Every one of them was dry fouled.
4. Replaced all spark plug wires with FRPP blue 9MM. Old ones had burned up in some areas where they were resting against the headers. New wires were rerouted to avoid that.
5. Throttle body was cleaned. It was filthy
6. Fuel filter was replaced. It was partially clogged
7. Installed MSD ignition box
8. Air filter was cleaned
9. Idle air control valve was checked and was replaced about 2 months ago.
10. Distributor cap and rotor were checked. No cracks, no carbon trail.
11. Ignition control module was replaced with a brand new Motorcraft one.
12. Distributor coil wire was replaced. It was severely corroded.
13. Distributor coil was checked and turned out to be good
14. Throttle position sensor was adjusted. It was set at .37 on idle and would not go above 3 volts at full throttle. I set it to .94 (that's all I could get out of it) at idle and 4.6 at wide open throttle.
15. Fuel pressure regulator was checked and is good. Reads 39 lbs of pressure
16. Replaced distributor rotor
17. Swapped out ECM
18. Replaced distributor
19. Replaced engine coolant temperature sensor
20. Set the timing to 10 degrees
21. Checked the timing chain. It is tight
22. Replaced fuel pump with 155lph
23. Replaced Fuel injectors
Here is what I have done. The issue has gotten better since doing all this work, but it is still there.
1. Both 02 sensors were replaced
2. Replaced the Mass Air Flow sensor
3. Spark plugs were replaced. Every one of them was dry fouled.
4. Replaced all spark plug wires with FRPP blue 9MM. Old ones had burned up in some areas where they were resting against the headers. New wires were rerouted to avoid that.
5. Throttle body was cleaned. It was filthy
6. Fuel filter was replaced. It was partially clogged
7. Installed MSD ignition box
8. Air filter was cleaned
9. Idle air control valve was checked and was replaced about 2 months ago.
10. Distributor cap and rotor were checked. No cracks, no carbon trail.
11. Ignition control module was replaced with a brand new Motorcraft one.
12. Distributor coil wire was replaced. It was severely corroded.
13. Distributor coil was checked and turned out to be good
14. Throttle position sensor was adjusted. It was set at .37 on idle and would not go above 3 volts at full throttle. I set it to .94 (that's all I could get out of it) at idle and 4.6 at wide open throttle.
15. Fuel pressure regulator was checked and is good. Reads 39 lbs of pressure
16. Replaced distributor rotor
17. Swapped out ECM
18. Replaced distributor
19. Replaced engine coolant temperature sensor
20. Set the timing to 10 degrees
21. Checked the timing chain. It is tight
22. Replaced fuel pump with 155lph
23. Replaced Fuel injectors
1 - 20 of 123 Posts
Read item number 2 on my listwhen you unpug the maf does it change the idle?
Did not try that. It's strange because it will not idle rough all the time. Worth a shot thoughwhen you unpug the maf does it change the idle?
Pulled the MAF sensor while it was running and it died instantly.
Not to get off topic, but when you replaced your control module, was the special wrench actually able to get into that tight space next to the distributor? I still don't believe that anything can fit there, let alone a wrench...
No, it did not. I had to rotate the distributor in order for the "special wrench" to work and even then it was kind of a tight spot.
I had a very similar issue on my old '95 GT. Tried a ton of things and the darn thing turned out to be mis-routed plug wires. Boy did I feel like a dumbass. Check 'em...it only takes a minute or two.
Plug wires are not misrouted.I had a very similar issue on my old '95 GT. Tried a ton of things and the darn thing turned out to be mis-routed plug wires. Boy did I feel like a dumbass. Check 'em...it only takes a minute or two.
Its been a long time since my last 5.0, but have seen similar issues.
I chased a problem for about a year that ended up being a worn dizzy. At higher rpm it would wobble and cause it to cut out a lot.
I chased a problem for about a year that ended up being a worn dizzy. At higher rpm it would wobble and cause it to cut out a lot.
now restart it and see what it does..go drive it. also, spray water on all the header primaries (while running) and see if any are cold...also check the center button in the cap and see if its severely worn. it needs to contact the rotor at all times...Pulled the MAF sensor while it was running and it died instantly.
I'm leaning towards worn distributor as well. When mine did this, I had found that my connection in between the pickup coil and TFI module had been getting very hot, would arc, and there wasa little corrosion beginning to build. I pulled the distributor and found the bushings were worn. Replaced it, and it was good to go.
Go drive it first, as Greenbullit suggested. I will ask why, though, Paul. I wouldn't think our archaic computers would pick up on that.
Go drive it first, as Greenbullit suggested. I will ask why, though, Paul. I wouldn't think our archaic computers would pick up on that.
I'm leaning towards worn distributor as well. When mine did this, I had found that my connection in between the pickup coil and TFI module had been getting very hot, would arc, and there wasa little corrosion beginning to build. I pulled the distributor and found the bushings were worn. Replaced it, and it was good to go.
Go drive it first, as Greenbullit suggested. I will ask why, though, Paul. I wouldn't think our archaic computers would pick up on that.
this will give an idea of what is causing the probs. by removing the maf from the picture,you allow the computer to run in "default". if it runs better, its most likely lean (and ran better because the injector pulsewidth was widened and acted as a bandaid) then the next issue is to find why (it doesnt mean the maf is bad)...if not, it could be a hego (which i doubt) or an ignition issue...the car has no codes? prolly not, but thought id ask...you can also run with the 02s disconnected (just like we did with the maf) as a diagnosis tool...
Mine had VERY similar issues, as I mentioned in your thread a week or two ago, putting another computer in fixed the issue completely. All the other things I did helped, but did not fix it. I realize you will have to find another computer to try it... but its definetly a possibility.
Ah, that's why I was wondering. He has to unplug it, then crank it up. When he stated he had unplugged it and it died, I ASSumed he plugged it back up. Then with your suggestion I was a little confused, as I couldn't correlate how the computer viewed this.this will give an idea of what is causing the probs. by removing the maf from the picture,you allow the computer to run in "default". if it runs better, its most likely lean (and ran better because the injector pulsewidth was widened and acted as a bandaid) then the next issue is to find why (it doesnt mean the maf is bad)...if not, it could be a hego (which i doubt) or an ignition issue...the car has no codes? prolly not, but thought id ask...you can also run with the 02s disconnected (just like we did with the maf) as a diagnosis tool...
If you need a distributor I have a good one PM me.
****UPDATE****
I advanced the timing as far as I could without it spark knocking. Did it this morning and it has run just fine all day.
I advanced the timing as far as I could without it spark knocking. Did it this morning and it has run just fine all day.
Well... the problem came back the day after I advanced the timing. Any other ideas guys. I updated my check down list in the opening line
Have you tried another computer yet... I know it makes no sense for it to go out... but mine did it!
Disregaurd that.. I just re-checked your list.
Checked all over for vacuum leaks?
Checked all your grounds... body, engine, ect.?
Disregaurd that.. I just re-checked your list.
Checked all over for vacuum leaks?
Checked all your grounds... body, engine, ect.?
yup. I swapped out the computer earlier today and I also installed an MSD ignition box. Same problem exists. When it starts freaking out, I can floor it and it will not go above 3k RPM and then all of a sudden it just goes back to normal. The only thing left that I can think to do to this thing is replace the fuel pressure regulator (but it reads 39 psi), replace the fuel pump and replace the distributor.
1 - 20 of 123 Posts
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