bbhall89

This car its giving me a headache. This is what I've done to this so far:
New tps, map, and maf
New fuel pump and filter
New to me brake booster
Tune up
So this is what its doing to me now, it wasn't starting but i figured out UT had a clogged fuel line. Its now fixed and runs smoothly at least idles. When i put it in park or neutral and lay on the throttle it accelerates and decelerates just fine but when i drive it it'll smoothly, slowly accelerate but if i try to throttle it faster it'll bog and spit at me till i let off the pedal.
My thoughts about this, bad crank sensor? Something wrong with the transmission or hopefully just a bad sensor on it. Bad cam sensor. Any feedback is greatly appreciated. Please help and also please keep in mind what I've done to it so far.

dave1123

Please inform us what vehicle and engine you are talking about.

bbhall89

Sorry, 94 jeep grand cherokee Laredo with a 5.2l 318 v8.

dave1123

It may be worn spark plugs. With a large gap, the spark can "blow out" under high cylinder pressures. Or your spark plug wires aren't delivering enough voltage. Check your ignition system; cap, rotor, wires, plugs for condition.

bbhall89

Even if I just gave it a complete tune up a month ago? To include plugs wires cap and rotor and I also replaced that disc under the rotor..I can never remember what it's called.

Bustedback

You may have a clogged catalytic converter. Put a vacuum gauge on a manifold vacuum port and watch it as you drive. If you see the vacuum decrease and you start to see pressure build in the manifold you have a restricted exhaust. Or you can remove the O2 sensor from the exhaust before the cat and go for a short drive. If it feels better without the O2 installed you have a restricted exhaust. I had a Dodge pickup at the shop that would not run at all. I checked the fuel pressure and found it to drop to zero in ten seconds, so I replaced the pump. I went to start it and it still would not start, but I did notice smoke coming from the air cleaner assembly. I removed the O2 sensor that was before the cat and started the engine. It ran, not very good, but it ran. Put a new cat on it and a complete tune up, it now runs like new. Check your catalytic converter.

bbhall89

Ok thank you I'll give that a shot tomorrow and see what it does and give an update after.

bbhall89

I tried what you said and it made the car run worse than it is. I'm not having trouble with idle really more the fact that the car won't shift if the rpms hit 2000. And once they do the engine spits and acts like it wants to back fire. So I'm leaning towards a transmission issue. If anyone could point me in the right direction that would be awesome. Thank you for the insight and idea tho.

bbhall89

And another thing. I checked the wires, cap rotor, all are just fine and look brand new. The plugs however look like the fuel mix is rich, and they have a kinda white/ light green deposit on them. Thoughts?