CoffeeCommando

1998 XJ, Limited
AW4 (4WD)
4.7 Stroker (I6)
MSD Ignition with High Vibration Blaster Coil
Autolites, .045 gap
ACCEL 8MM Plug Wires
1.6 Yella Terra RR's
Magnaflow Exh.
K&N Intake
FlexAlite Fans
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All New Sensors (MAP, TPS, IAC, CKS, Distributor with CPS)
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Here's a brief history on what I have done recently.

I had a wideband 02 hooked up that I couldn't check the settings on and have set up because I misplaced the proprietary cable that you had to use for your laptop.

So in the end I disconnected it and hooked up the original 02 sensor. I had previously used the original wiring from the 02 sensor to splice onto the aftermarket. When I rewired it all back up I had my ground and 02 signal criss crossed, so the PCM always sensed lean and ran me extremely rich.

I went through two brand new 02's before I figured that out and wired it up the right way. During that time I always had the code for it running too lean on exhaust bank 1. I also had loss of crank or cam (1391).

After fixing the 02 that left me with just the 1391 problem.

With the rich'ture running problem out of the way, any time the engine reaches operating temperature it idles like crap. I still have 1391 code problem.

EVERY time I turn it off and turn it back on, regardless of operating temperature, about 40 seconds into driving I find that when I decel through the 1800-1500 RPM range and try to accelerate... it just remains at that RPM. It only budges when I give it WOT, and then it reponds fully. If I ride it up to 4000+ RPM it will go away until the next time I drive it. Sometimes I have to shift it in to nuetral to get it to 4000.

Also, sometimes it will crack/pop when it does it (sounds like it's coming from the exhaust down pipe, and I can feel it in the accelerator pedal). It doesn't do it all the time. Usually when it's being more stubborn. It ALWAYS hesitates before it takes off with the WOT.

... then when I'm idling, just out of the blue, the RPM will slowly start dropping. Then it shoots up to 1000 (i'm guessing that's the IAC adjusting for the loss). Then it will constantly bounce back to 1000 every time it reaches 750 while I'm idling. It will stay that way until I'm done driving.

..all the while, I still have the 1391 code for loss of "cam or crank". BOTH sensors are new, and I've tested the crank so I know it's good. Didn't find any test procedures on the CPS... but then again I don't see how it needs it since it just sendes an electrical pulse... which is mechanically designed. And I've looked at it. There's nothing wrong with it. So it doesn't seem like it could be that at all.

I was just looking in the manual and noticed there is one wire that is commong between the CPS, CKS, MAP and TPS however... it's an Orange wire on mine (the Hayne's says Blk/LtBlue for some reason..). Is that a power wire? Or something more important?

I think what I would like to know about most is... what exactly does the computer start doing differently when it reaches operating temperature?

Something else to take into consideration as well is that ever since I have had it rebuilt it hasn't had a perfect idle. It doesn't sound even. I'm about to go check out the yellas.

93gc40

Did you have the Computer flashed after the stoke job.. I have always heard you need to do that, or it will never run correctly.

CoffeeCommando

What exactly is a flash? Who can do it?


I'm pretty sure that's not the problem though. I've seen it idle perfect before. It was short lived after we re-TDC'ed it though. After it reached operating temperature it went back to normal uneven idling.


I just pulled off the valve cover and found that the number 4 intake rocker wasn't moving as much as the rest were...

As in, it had a smaller amount of stroke.

CoffeeCommando

Alright. I just checked injectorial spray. All was well. The number 4 injector had a torn O ring. I replaced that. Seems like it idled a tad better.

Now I have codes P0123 and P0505. Idle Air Control malfunction and High Circuit voltage on the pedal. I just reseated it like you're supposed to with pressing the button, and it previously wasn't seated all the way on the throttle plate either. I'll clear those up and inspect that idle air. I had to glue it to get it to fit in there because the IAC housing had a stripped out bolt hole.

I think doing shady work all in all is what's causing the majority of the problems. I can't help it though.. being parked undeneath a shade tree.