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Unread 08-17-2011, 06:28 AM   #16
robin1t2002
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Quote:
Originally Posted by CJ7-Tim View Post
From one of the on-line Jeep part departments. Some of the Dealerships do Internet parts sales. 30% of the retail price for Genuine Jeep parts.

Do you have a link to one of them. I want to pick up a good spare CPS and need some other OE parts. I don't want to get gouged at the local dealer.

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Unread 08-17-2011, 07:01 PM   #17
rsurran
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Here is one I found but not bought anything there yet. This place is near me (sort of) if I have a problem:

http://www.moparpartsworldwide.com/
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Unread 08-17-2011, 10:07 PM   #18
CJ7-Tim
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http://chryslerjeepdodgeparts.com/

http://www.trademotion.com/partlocat...?siteid=214583

http://wholesalemopar.com

http://www.trademotion.com/partlocat...?siteid=213674

www.jeeppartsdept.com
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Unread 08-18-2011, 04:31 AM   #19
rsurran
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I'm tempted to go all MOPAR for my Jeep (WalMart carries some) but then most of the guys on the Forum are using after-market parts they think are better/cheaper such as the Goodyear Gator Back belts, Rotella oil etc. Choices, choices. Seems like it would be cool to say my Jeep is all Jeep.
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Unread 08-18-2011, 09:20 AM   #20
xjmw
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NO SPARK,Replaced our CPS still not starting, Fuel relay????

We have a 2000 jeep cherokee, one day we went out tried to start it and all it did was crank and crank, listened for the fuel pump.. nothing. so we started with testing and replacing the cps. This did nothing it still just cranks. when we test the fuel pump it was fine but we arent getting any pressure so we tested the fuel relay and get power but on the other end we have an open circut, so when by pass the relay and start the pump manually its still not starting, thinking whatever it is has to run our injectors as well? any ideas anyone we are at a loss on this one
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Unread 08-18-2011, 09:33 AM   #21
CJ7-Tim
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The engine computer looks for the CPS signal. A short circuit or an open circuit wire looks the same as a failed CPS. Inspect the under hood wire harnesses for corroded or damaged wire connectors and for chafed or melted wire insulation.

Inspect all the fuses in both the fuse boxes and swap around the similar shaped relays. Find out where and why you have the open circuit.
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Unread 11-09-2011, 06:35 PM   #22
viperfanatic13
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when my cps failed the coil also went with it. bought a new cps still had the same problem then bought a new coil and it fired right up. check to see if the coil is sending spark.
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Unread 11-09-2011, 06:37 PM   #23
viperfanatic13
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Quote:
Originally Posted by xjmw View Post
We have a 2000 jeep cherokee, one day we went out tried to start it and all it did was crank and crank, listened for the fuel pump.. nothing. so we started with testing and replacing the cps. This did nothing it still just cranks. when we test the fuel pump it was fine but we arent getting any pressure so we tested the fuel relay and get power but on the other end we have an open circut, so when by pass the relay and start the pump manually its still not starting, thinking whatever it is has to run our injectors as well? any ideas anyone we are at a loss on this one
when my cps failed the coil also went with it. bought a new cps still had the same problem then bought a new coil and it fired right up. check to see if the coil is sending spark.
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Unread 11-09-2011, 06:45 PM   #24
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i am having the same problem with mu 92 wrangler. it died on me and would crank but wouldnt start. the coil went out to. i bought a new cps and coil and it fired right up, ran for about 2 to 3 minutes then died and now im back to square one. i read that someone had the same problem and he unplugged it and replugged it back in and fired up, his ran for about a month and he would have to do it again. i tried this and it fired up but died again after a couple minutes. any thoughts? i put a jet performance chip in it a few months ago, could that be connected somehow?
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Unread 11-09-2011, 06:45 PM   #25
tjwalker
It's the crank sensor!
 
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I buy plenty of aftermarket parts, but I buy my crank sensors ONLY, ONLY, ONLY (enough emphasis?) from Jeep.

It is worth every extra penny you will spend.

I can't tell you how many threads I've been involved with where there are problems with an aftermarket crank sensor. Don't go there.
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Unread 06-23-2012, 08:40 PM   #26
djtricia
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Cranks over longer before starting, CPS trouble

I've noticed my 98 with the 4.0 cranks over longer before starting. It always starts but doesn't fire up right away like it used to. Had the CPS replaced last summer and I think the mechanic bought it at Autozone. The Jeep had 220,000 on it then and now has 227,000. I also know the cat needs replacing and the exhaust manifold has the typical crack in it. Any thoughts?
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Unread 06-24-2012, 05:52 AM   #27
tjwalker
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Quote:
Originally Posted by djtricia View Post
I've noticed my 98 with the 4.0 cranks over longer before starting. It always starts but doesn't fire up right away like it used to. Had the CPS replaced last summer and I think the mechanic bought it at Autozone. The Jeep had 220,000 on it then and now has 227,000. I also know the cat needs replacing and the exhaust manifold has the typical crack in it. Any thoughts?
Would be a good idea for you to start a new thread. It's less confusing to others and you'll get more replies targeted to your exact issue(s)

Your extended crank time is most likely related to a bad check valve in the fuel pump assembly. A VERY common failure on your vintage.
------------------------------------------------------------------
The check valves (there are two of them; one on the fuel pressure regulator and another on the fuel pump) are part of the fuel pump assembly on 95.5-2001 vintage 4.0 XJs. When a check valve starts to fail, it can reduce fuel pressure to a point where an extended cranking time is needed to start the engine. It is a very common failure. I experienced it on my 99 at around 75K.

A good (and simple) first step in helping you troubleshoot this problem is called “the poor mans prime”

1. Turn key to ON position (do not crank the engine!)
2. The fuel pump will energize and run for a couple of seconds
3. Turn key to OFF position
4. Repeat above steps 1-3 two more times
5. NOW crank the engine over

If the engine starts quickly and cleanly after performing this procedure, you may have a check valve issue. If it starts and runs poorly for a few seconds, it could also be a leaky fuel injector resulting in the fuel pressure leaking down and the subsequent stumble upon startup is the engine clearing the excess fuel that has leaked into the cylinder because of the faulty injector.

Also be aware that a bad battery can give you starting symptoms as well. Have your battery load tested (any parts store will do this for free) if you have any doubt; your XJ does NOT like low available battery voltage. Be sure battery connections and posts are CLEAN.

Some troubleshooting tips for extended crank times. You will need a fuel pressure gauge. Many parts stores will rent you this tool inexpensively.

*Hook up fuel pressure gauge on the schrader valve on the fuel rail under the hood

*Start engine and bring to normal operating temperature.

*Observe fuel pressure gauge. Normal operating pressure should be 49.2 psi (plus or minus 5 psi)

*Shut engine off.

*Observe pressure on gauge. Pressure should not fall below 30 psi for five minutes.

If pressure falls below 30 psi, it must be determined if a fuel injector, a check valve within the
fuel pump assembly, or a fuel tube/line is leaking. An adaptor tool/hose included with the fuel pressure gauge can help you with this. Consult the manual that comes with the fuel pressure gauge and the Factory Service Manual for your year XJ for more information on this exact procedure, but here is basically how it works:

*Turn the engine off and immediately clamp the fuel line at the adaptor hose. Watch the pressure gauge and see how long it takes to lose pressure.

*If the pressure remains at 49 psi for an extended period of time then the problem is in the tank – most likely a check valve. If the pressure falls below 49 psi fairly rapidly then the problem is probably a leaky fuel injector.

**Note. Where check valve is suspect, a quick loss of fuel pressure is often the fuel pressure regulator check valve and a slow loss of pressure is often the fuel pump check valve. But keep in mind that either or both check valves can be to blame.

You can limp a check valve problem along indefinitely if you like, as it doesn't mean the fuel pump itself is going to fail. Perform the “poor mans prime” before cranking to speed up your starts. However, if you have a check valve issue and want to resolve it, it is recommended that you replace the entire fuel pump assembly for two reasons. First, you have to drop the gas tank to access the assembly. Secondly, with two check valves, replacing just the fuel pressure regulator where one of the check valve resides may or may not resolve your problem; remember there are two check valves; the other one is on the fuel pump.

The fuel pump assembly consists of fuel pump, fuel pressure regulator, fuel gauge sending unit, fuel gauge float, pickup filter and pigtail wiring harness. If you do replace the fuel pump assembly, purchase a high quality unit; you do get what you pay for here. Some cheap aftermarket assemblies have been known to fail prematurely. I personally prefer Bosch fuel pumps as they manufacture the best fuel pump assemblies for the XJ. Carter is my second choice. Airtex is my least favorite choice and I will not recommend or install them.
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Unread 06-25-2012, 08:26 PM   #28
djtricia
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Extended crank time

Thanks for all the info. I've noticed if I shut it off and restart it will fire right away. So sounds like your diagnosis is right.
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Unread 08-27-2013, 02:28 PM   #29
QESdunn
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I see Crankshaft position sensors on eBay for as little as $15 and as much as $80 listed elsewhere; what's the difference?

http://www.ebay.com/sch/i.html?LH_BI...sensor&_sop=15
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Unread 08-27-2013, 03:40 PM   #30
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I see Crankshaft position sensors on eBay for as little as $15 and as much as $80 listed elsewhere; what's the difference?

http://www.ebay.com/sch/i.html?LH_BI...sensor&_sop=15
Just go get one from Napa. Their Premium line. $15 ones are JUNK.
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