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88fadedglory · 03-11-2010, 11:54 AM

Prob. #1

88 XJ, Renix 4.0, BA10/5, no cat, CherryBomb turbo muffler.

Engine quit three times, twice while driving and once, this AM, while warming up the oil in the BA10/5 so it would shift easier.

I had to "reset" (pump the gas with the key on then crank the engine) the TPS the first two times to get a restart, but the TPS has less than 2K miles on it and it is adjusted correctly.

This AM, the "reset" didn't help, but gas pedal flat to the floor got it running again, but it then had a lot of hesitiation coming off idle.

Suggestions???

Prob #2

No heater fan in any position. Fuse good. Might work the next time I start the engine, might not. I suspect the switch on the heater / vent / AC is about to go bad.

Suggestions???

4.3L XJ · 03-11-2010, 12:09 PM

Check your crank position sensor Budd.

I vote switch for the heater fan too.

BACKWOOD · 03-11-2010, 01:01 PM

will it stay running or die in less than 30 seconds?

88fadedglory · 03-11-2010, 01:43 PM

Quote:

Originally Posted by 4.3L XJ

Check your crank position sensor Budd.

I vote switch for the heater fan too.

Thanks, will do.

But it's going to have to wait till the weather warms a bit ... no garage.

88fadedglory · 03-11-2010, 01:45 PM

Quote:

Originally Posted by BACKWOOD

will it stay running or die in less than 30 seconds?

Once it restarts, it's fine until the next time. From the first failure to the second was nearly a month and from 2 to 3 was a couple weeks.

I drove the better half to work this AM with only the hesitation as a "problem" and that smoothed out after the engine warmed up.

4.3L XJ · 03-11-2010, 02:12 PM

Budd

Many times that is just how those CPSs behave when they go. If you have an ohm meter, unplug it and check for resistance across the two wires. If there is it is shot.

88fadedglory · 03-11-2010, 03:07 PM

Quote:

Originally Posted by 4.3L XJ

Budd

Many times that is just how those CPSs behave when they go. If you have an ohm meter, unplug it and check for resistance across the two wires. If there is it is shot.

Both Chilton and Haynes says there should be 175 - 250 Ohms resistance with a hot engine.

4.3L XJ · 03-11-2010, 04:41 PM

OK, I'm bassackwards

88fadedglory · 03-11-2010, 05:10 PM

Quote:

Originally Posted by 4.3L XJ

OK, I'm bassackwards

Don't be too quick about that ... I started to torque a set of rod bolts to a figure given in a manual and they had the main bearing cap bolt / rod cap bolt numbers swapped.

But I caught it before I stripped off a rod bolt.

Just to be on the safe side, though, I went and got a new set from NAPA. 318 rod bolts fit Slant Sixes . . . . . . and they're a bit cheaper.

Is there a place to check it without crawling under the rig? My manuals don't really give much help there.

4.3L XJ · 03-11-2010, 06:32 PM

The CPS is on the top right? I am guessing here because I don't have one. I think the plug is accessible in the engine bay. Although getting under it is the way to change it.

Try this Crank position sensor - NAXJA Forums -::- North American XJ Association

thaspyder69 · 03-11-2010, 09:53 PM

Check for buildup in the throttle body also. I had a similar problem. Cleaned the throttle body and the problem went away.

88fadedglory · 03-11-2010, 10:46 PM

Quote:

Originally Posted by thaspyder69

Check for buildup in the throttle body also. I had a similar problem. Cleaned the throttle body and the problem went away.

I'll pop the intake tube and check it, but I cleaned it just last fall.

88fadedglory · 03-11-2010, 10:57 PM

Quote:

Originally Posted by 4.3L XJ

The CPS is on the top right? I am guessing here because I don't have one. I think the plug is accessible in the engine bay. Although getting under it is the way to change it.

Try this Crank position sensor - NAXJA Forums -::- North American XJ Association

Would that be the plug to the module under the coil with three wires?

I think the easy way to get to the CPS to change it will be to drop the trans crosmember a little with the trans still bolted and angle the back of the engine down a little ... probably have to drop the exhaust downpipe too.

88fadedglory · 03-27-2010, 01:36 AM

Got the CPS checked both hot and cold and it's within limits, but, the darn plug was a bit loose.

Haven't had a single hiccup since my last post and fuel economy appears to be up a bit.

That said, it'll probably quit tomorrow. . . . . . . . .

88fadedglory · 03-31-2010, 02:42 PM

I went to sell some scrap steel today and when I restarted the engine on the weight scale, it ran poorly, like it was rich and died. It repeated twice more.

So when I got to where to drop off the scrap, I left it running and since then it's started and ran fine twice more.

I was towing a 1/2 ton capacity trailer with 300 pounds of scrap on it with my 88 Cherokee 4.0, BA10/5, 3.07 axles.

Never a dull moment with a Renix system . . . . . . .