I Need Help

[wcchmp88]

I have a recently purchased 1990 Bronco. When I first bought it I had a miss after I drove it a few miles. I changed plugs,wires,cap,and rotor button and it ran great.By the way it has a 94 302 in it. My problem is, I decided to clean the engine and while I was cleaning it started running rough and shut off. It will not stay cranked unless I keep it running at about 1000 rpm and it is still very rough. When I rev the engine to 3000 or so it sounds ok. I checked the cap,plugwires,etc. everything looks fine. I also looked for a vaccum line but all seems well. Could the coil cause this? Any help would be appreciated.
Jeff

 

[Shadow_D]

Welcome to the "B" Zone!

I would say the best thing to do is finish the tune up. I say this because people always seem to forget the O2 sensor, PCV, and coil.
See how it runs after you change them and let us know.

 

[Brian]

ShadowD you replace the ignition coil as part of the tune up to? Thanks Brian

 

[wcchmp88]

I removed the vaccum line to the egr valve and the truck runs fine now. What is the best way to determine if the valve is bad or the sensor? Thanks for the help.
Jeff

 

[Guest]

That being the case, I would check the lines in the control circuit for the EGR. If you don't have a Ford EVTM get a Chiltons. You probably either knocked something loose or got water in something. On your truck, the EGR is computer controlled via the EGR Solinoid which controls vacuum to the EGR valve when required. This recycles small amounts of exhaust gasses back in to the combustion system under set conditions to reduceNitrous Oxide. The ECC looks at temp, rpm, throttle opening aswell as a sensor on top of the EGR that tells how far the EGR is open. With these inputs the ECC controls the amount of vacuum to the EGR by adjusting the amount of vacuum to the EGR.

Good Luck,

>-

 

[Seabronc]

PS the EGR valve should only operate at the part-throttle mode, it should be closed at th cranking mode, the closed throttle mode, and the wide open mode.

Good luck,

 

[Shadow_D]

The coil is the last thing I replace. If it seems to run bad after a tune-up I replace that and that seems to fix it.

 

[Justshootme84]

If you wash the motor and get ANY water in the alternator, things can go awry. I think that is the source of your problems.

 

[Broncoholics]

Sometimes its hard to see the slight moisture in the distributor cap. Try spraying it with WD40 or wipe it out.