97 TJ wont start

My 97 Wrangler Sahara 4.0 AT has quit running. Leading up to this, there were a couple of mornings when the idle was rough and I wuld have to keep my foot in the gas a little to keep her going but after a bit it would go fine. Then, last week at work, I started up and started to back out when it stalled. I opened the hood and jiggled and banged on everything I could see and checked all the fuses. Still nothing. Then after about thirty minutes, it just started up and ran home. The next day it wouldn't start and hasn't since. I noticed today that the fuel pump is running constantly while the key is in the on position and there is definitely fuel pressure at the rail. I pulled the coil wire and I'm not getting any juice to the distributor. Anyways, after reading around a little, i'm leaning to replacing the crank position sensor. Does anyone have any additional advice? Could a malfunctioning CPS make the brain think the fuel pump needs to run constantly? Any help is appreciated....Rob

Reply to
rs
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Sorry, I forgot to add that I tried to pull the codes by turning the ignition on-off-on-off-on, but nothing happened...

Reply to
rs

I would start by using a spray contact cleaner or even WD40 on the electrical connections for the TPS on the throttle body, then the CPS plug for the flywheel one and the CPS plug for the distributor one.

My guess is the TPS connection...

One other thing that can cause something like that is the mesh strap from the rear of the engine up to the firewall or it's connections. If you live in the rust belt, these tend to fail early.

Mike

86/00 CJ7 Laredo, 33x9.5 BFG Muds, 'glass nose to tail >
Reply to
Mike Romain

Mike Romain did pass the time by typing:

That's usually the culprit.

That and a dead coil. Coils are cheap and even if it doesn't fix the problem you now have a spare. Although on mine it usually fails to start or bucks when the coil is going.

The ASD relay will remove power to the coil if the engine fails to start in 2-3 revs or if there is no CPS sensor input for more than a couple of seconds.

Reply to
DougW

Reply to
L.W.(Bill) Hughes III

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