big loss of power

i recently replaced a noisy dist on a friend of mines 96 4.0 cherokee.we got a autozone dist for a 94 but it didnt look like the one we took out.the one for a 92 looked exactly the same so we got that and a new cap rotor wires and plugs.it idled fine (i had to manually find tdc and reset the position of the dist)and a quick trip around the block seemed like all was well.
he tells me that it seems to have a very late upshift and a severe loss of power at higher speeds(above 45)
we took it for a ride tonite and he is right.it idles fine so i assume i have the dist in correct but when you give it gas the rpms go up but the speed barely increases.in fact if you let off on the gas a bit it goes a little faster.it also starts pinging at the higher rpms.this jeep has a new cat and muffler so i dont think that is the problem.things seem to be fine back at the tailpipe when he revs it and i hold my hand near it.it also is throwing no trouble codes at all.it has a new airfilter and i even pulled off the inlet tube and took a ride just sucking in direct air and it was the same.
does anyone have any ideas or any advice as to what to look at next?

i also took the tv cable off of the throttle to get a hose under it when we did the dist.originally i thought this might be the problem but i reset it tonite and it did not help this problem.

Sounds like your timing may be off, and the tranny might be low on fluid. You say that if you're in gear, and start to rev it, the RPM's go up but the jeep doesn't move much? Definitely check the fluid then. Torque converter might not have enough to work properly.

thanks,i forgot to add that i checked the trans fluid and it seemed fine.up to the correct level and somewhat red (not burnt)

Check the Vtec solenoid.

I don't understand auto's too much, but could it be stuck in a higher gear? Try manually selecting "1" and see what happens.

thanks for the replies.
what is the vtec solenoid?
and shifting it manually has the same results.

is there some way i can check for a cloggged exhaust without actually pulling it down?it has a new cat and muffler from the po but is all welded

markg said:

is there some way i can check for a cloggged exhaust without actually pulling it down?it has a new cat and muffler from the po but is all welded

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Unbolt the downpipe where the header exits.

Or briefly remove the o2 sensor and test it. When it's cold. If you do it hot you'll likely set something on fire. Course, the little O2 bung won't allow full flow but would bring back some if its clogged.

Did you reconnect the cam sensor?

cam sensor??????

doesnt the dist only have one plug to plug in?
or am i thinking of something different.

the dist i put in looked just like this one.i did not put anything from the old into the new.was i supposed to?the 1st dist i bought looked different and had more stuff in it but did not look like the one i took out at all.thats why i got one from a 92.....because it looked exactly the same.













http://img261.imageshack.us/img261/2041/distributerindex4lj9oo1.jpg

I was thinking a bad TPS until you said it acts the same way in 1-2 position, but disconnect the power fuse to the TCU computer, and retest it in 1-2 position to confirm it is not a bad TPS.

There is a vacuum operated fuel pressure regulator on the fuel rail. Get the fuel pressure tested during acceleration (maybe try in Neutral to add some load to the engine) to see if fuel pressure / flow is dropping off. Check the vacuum line to the regulator, see if there is gas in it (leaking FR diaphragm), or of it is loose or has come loose.

Could be a tranny problem, but they are rare.

Does not sound like an ignition problem, sounds like fuel, TPS, or tranny problems or blocked exhaust, and sounds like he elliminated the blocked exhaust possibility already.

thanks
ill look into all of these and report back.

nw-xj-scott said:

Check the Vtec solenoid.

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... wtf?

If the problem wasn't there before the distro change, then I'd still think that the fuel sync is off a bit and try moving the distro a tooth in both directions and give it a test drive.

What symptoms caused you to change the dizzy in the first place? Are those symptoms gone now? Are you suprised that an Autozone dizzy might be bad?