87GT006

I own a 87' 5.0 GT and I have had the car relatively long, basically since it was about at 40,000 miles. recently, I have been having this problem with sort of a backfire when I hit the throttle. The car is relatively stock. so I cant see it being anything performance related. I have knocked my head around this problem for about 3 weeks now and it almost makes me sad when I go to hit the throttle, and the car gets to about 3,000 rpms and than it suddenly hold back power for a second and than kicks like a mule forward . I ahve debated if it was a fuel delivery related problem or simply a lack backpressure somewhere in the exhaust. To better describe what happens, lemme try this.

"I am cruising around town, casually changing gears around 2500-3000, and than I feel the need to get on it a little, so I figure I will rev out 1st for a little extra noise and head nods. So I hit the pedal, and the car shoots to 3000 than it feels like the car basically ran into a sand pit for a second, and than suddenly jets off similiar to the backfire somewhat. " (no actual backfiring) . It really sucks when you dont know when this is going to happen, and my 10+ years of mechanical savvy cant seem to grasp it. has anyone else had this problem or know how to deal with it? any suggestion or help would be appreciated.

anthonydalrymple

Okay, KISS=Keep It Simple Stupid. Live it, learn it, & love it. My mantra if you will.....
a) Have you pulled codes yet? KOEO show anything? KOER show anything?
b) Anything you haven't serviced recently? Checked for the obvious like ign cap(for wierd carbon tracking), ohmed out the wires for high resistance or obvious burn marks, checked for a fouled plug amongst amongst a bunch of clean ones, replaced the fuel filter in the last year, vacuum leaks, exhaust leaks, cleaned the maf elements, cleaned out the throttlebody, etc?
c)Finally decide to pull the codes.....

65coupe88hatch

Try changing your fuel filter, they are usually around 10 bucks and simple to change

snjracer

I had a similar situation on my 91 Mustang 5.0. There is a screen on the electric fuel pump in the gas tank that broke, and that was clogging up the pump. It got to the point where
it would start stalling. But the first symptoms sounded similar.. It would shudder like it was starving for fuel, then suddenly kick in.. Can't say if your problem is the same, but it's
something to consider.

Poobs

I agree with the above. Check the maint, items first.

This happens with the car fully warm ?

Loss of power could be fuel related since you basically need more fuel as you get on it. It could also be ignition timing lagging as you rev up. So check filter, vacum leak, dist cap/rotor.

The 87 88 had a tendency to gunk up the general area where the EGR idle motor are, Carbon will build up in the EGRpassage too. It typically affects the idle but you could be just " lucky"

There is also a little screen under the PCV valve. It is a bear to get to, If there is too much blow-by it can clog and interfere with the PCV valve action.

The codes will hopefully also tell you stuff going on.

good luck