Dearborn5.0

I put 100 miles on the mustang yesterday.

The car ran great. Good Idle, Good response.

However, I noticed that under high load, the engine bogs down between 3500 and 4500 rpm. It would pull hard and then "fall on its face" It seemed to misfire or something.

Just gave it a tune up (cap, rotor, plugs). The wire are not new, but they tested okay (under 25000 ohms per foot).

I got a TPS code (code 23) on the KOEO test, but only on the hard codes and not on the continuous codes. ( I dont really believe the computer codes)

So what can cause this bogging down condition?

nitrous_bob

what do your plugs look like ? what kind are they ? check the gap and gap them about .035 to check things out. if it cures the problem, replace the plugs.

also check for a bad connection, or burned wire on the header , sometimes you think the wire is on, but it's not all the way.

Twister

I agree with you until the gap, not every year of Mustang had the same gap, the factory spec on the 86 was .050 to .054, so check your underhood sticker for that

mrbigshot

check your fuel filter, it sounds like its running out of fuel up top

nitrous_bob

yeah i know.... but if it's losing spark w/ a gap of .054" and the problem goes away when you close it up, the plugs are probably bad.

i also had this problem w/ bosch platinums, exact same problem, closed the gap up, it ran fine. replaced them w/ stockers and i was good to go.


if the problem is still there, it basically eliminates spark as being the problem, and i would start to look at fuel issues.