4.0L missing
Elder User
Joined: Apr 2005
Posts: 882
Likes: 0
From: Wichita
Have you tried whistling for her?
Hopefully yours is simple. I've had a pretty consistent miss at idle for some time. I'm at 110K on my '93 4.0. Plugs, wires, O2 sensor, Seafoam, etc haven't seemed to help. I'm wondering if I don't have a bad injector or valve problem.
Hopefully yours is simple. I've had a pretty consistent miss at idle for some time. I'm at 110K on my '93 4.0. Plugs, wires, O2 sensor, Seafoam, etc haven't seemed to help. I'm wondering if I don't have a bad injector or valve problem.
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
vango,
good technique for finding failed injector on bank injected systems is pull wire off injectors one at a time....run and check for worse miss....can be slow process but does pinpoint to failed plugged injectors
Aero injectors respond well to either Regane or the new Chevron Pure cleaner 20 oz in half tank....
good technique for finding failed injector on bank injected systems is pull wire off injectors one at a time....run and check for worse miss....can be slow process but does pinpoint to failed plugged injectors
Aero injectors respond well to either Regane or the new Chevron Pure cleaner 20 oz in half tank....
Postmaster
Joined: Sep 2003
Posts: 4,452
Likes: 1
From: Southern California
Missing at idle
Gentlemen:
Check your exhaust! I have been chasing an apparent idle miss on my 3.0L for over a year now without any success. Then someone here suggested that a leaky exhaust manifold coul be the problem. Sure enough, that was my case. One of the bolts on the exhaust manifold (way in the back) worked itself loose. I tightened it up and that seemed to have corrected the problem and gave me much better gas mileage also.
Check all the joints before the O2 sensor. That might be where you may find your problem. Who would have thought!!!!!!!!!!
Check your exhaust! I have been chasing an apparent idle miss on my 3.0L for over a year now without any success. Then someone here suggested that a leaky exhaust manifold coul be the problem. Sure enough, that was my case. One of the bolts on the exhaust manifold (way in the back) worked itself loose. I tightened it up and that seemed to have corrected the problem and gave me much better gas mileage also.
Check all the joints before the O2 sensor. That might be where you may find your problem. Who would have thought!!!!!!!!!!
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Post Fiend
Joined: Oct 2005
Posts: 5,242
Likes: 0
From: Kiev, Ukraine
On GM cars I used to add 2 variable resistors to o2 sensor circuit to calibrate voltage and fuel/air mixture. Sometimes nearly new O2 sensor reads a bit incorrectly (you can see it with exaust analyzer) and I can calibrate for 0.1-0.2Volt its signal.
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Senior User
Joined: Apr 2004
Posts: 312
Likes: 0
From: Lanham,MD
Well mines is still missing too. And I have never put a Ford in the shop for repairs ,allways do my own work but can;t seem to fix this so I will be junking it next week. Owned Fords for over 20 years.
Senior User
Joined: Apr 2004
Posts: 312
Likes: 0
From: Lanham,MD
Well looks like she be around a little longer. After testing every sensor and all 60 pins and the eec-IV harness the problems was the New Motorcraft plugs shorted out somehow. SP-486(AGSF42-PP) Installed my old and slightly worn Autolite AP765PP and it runs fine again.
Post Fiend
Joined: Apr 2005
Posts: 5,720
Likes: 5
From: Washington state
B,
did all the new fine wire MC plugs short
tell us more, the old Autolite double plats are nearing end of production if not already and we all will be stuck using expensive Iridium fine wires
did all the new fine wire MC plugs short
tell us more, the old Autolite double plats are nearing end of production if not already and we all will be stuck using expensive Iridium fine wires
