timing off, how and what next?!

after i traversed through a deep mud hole and spun the tires quick resulting in high rpms, my 86 cherokee 2.5 was running like the timing was off

well no adjustablillity of timing has left me clueless of what to do now, help me!

Sounds like you may have floated a valve. Did the problem clear up? If not, you may have collapsed a lifter. The only good thing is that on a 2.5L you can pull the lifters without pulling the head.

If the engine is getting old, you could have slipped a tooth on the cam timing chain. If it is not the case, you may have floated the valves, kissed the piston and now have a bent valve or a ported piston.

If the problem did not clear up, do a compression check and then post the figures.

well the engine is freshly rebuilt in the past 10k miles, and i also threw on a new timing gear and chain so ya, well ill check it all out anyways

Doesn´t take much moisture in the high voltage wires, the cap or even in sensor connectors to cause ignition problems.
Plugs can fire at the wrong time, often blows back through the carb. First thing I´d do is pull all the plug wires and blow out the contacts with air. Same with the distributor. Fire it up, at night and look closly at the high voltage wires, if it´s pretty dark, you can see the high voltage taking strange paths to ground or where ever.
Water in the ignition, is one of the frist things to check. Takes very little moisture, even water vapor will mess with you.
If the ignition system checks out and the basics are OK, fireing order etc. a TDC check and/or a compression test would probably be next.
If you got any water in the intake a deformed or bent valve is possible (if your lucky).

xxXjxx said:

after i traversed through a deep mud hole and spun the tires quick resulting in high rpms, my 86 cherokee 2.5 was running like the timing was off

well no adjustablillity of timing has left me clueless of what to do now, help me!

Click to expand...

Have you confirmed that the timing is off? Have you taken a timing light to it?

nah i didnt hit it with the light, as far as ignition i replaced coil, cap, wires, plugs, ignition module, map sensor, o2 sensor, and it still ran the same.

One way to make sure your timing is close enough, is to take the number 1 plug out and with a compression gauge (or the old thumb) run it up to TDC compression. I use a slightly bent piece of welding rod to make sure I´m at the top. Check and see how close your timing mark is, then look and see how close your rotor is to number one on the cap. It doesn´t have to be exactly at the "1" on the cap but close.
Make sure you are at TDC compression, before changing anything. The exhaust stroke can build a little pressure that may fool you.
When your sure, the motor is at "1" TDC compression, look at your number one rockers, you should be able to wiggle the rocker arms a little and they should be close to level with each other. There is very little tension on the "1" rockers, when the motor is at TDC "1".
Which 2.5 do you have?
I had what I originaly thought was a timing problem, turned out to be a bent valve. When I was sure the ignition was in order, you could see it with a vacuum gauge, needle swung pretty far at a regular interval. Did have one cylinder with a slightly low compression, but the valve never did completely unseal.
I ran each cylinder up to TDC (top of the compression stroke) and I could see that the rocker arms on the affected cylinder, weren´t level and/or looked different than the others.