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Topic Review (Newest First)
01-12-2012 06:49 PM
BigGreen98 Ok changed crankshaft position sensor and I'm good to go
01-11-2012 06:18 PM
BigGreen98 So I just pissed that money away! New comp in and still no start
01-08-2012 07:35 AM
BigGreen98 Ok so the scan tool he had couldn't even find the computer. So I ordered one off e bay for 250, do I guess I'll just sit and wait with my fingers crossed
01-07-2012 07:29 PM
jkp
Quote:
Originally Posted by muherd50 View Post
Just last night got mine running right again. Wouldn't start....discovered it would run great after a shot of starting fluid to get it going. Posted on here and it was suggested to clean the TB...more specifically the IAC. That was my problem. Tried cleaning it while it was still on by spraying TB cleaner in the slot for the IAC and it was better but didn't fix it. I took the TB off and apart to clean it thoroughly and wow what a difference. It runs better than it ever. Love the WF!
If you have the stuck IAC, you can get it running by depressing the accelerator pedal a little and then cranking the engine. You will have to keep the throttle depressed a little or it will die. Easier with an auto than a stick, but I managed to get my 6 spd home from the hunting club this way.
01-07-2012 09:37 AM
cthies PLEASE post what the mechanic says! I am still searching for Gremlins under my TJ.....

Damn things are hard to find.
01-07-2012 07:58 AM
muherd50 Just last night got mine running right again. Wouldn't start....discovered it would run great after a shot of starting fluid to get it going. Posted on here and it was suggested to clean the TB...more specifically the IAC. That was my problem. Tried cleaning it while it was still on by spraying TB cleaner in the slot for the IAC and it was better but didn't fix it. I took the TB off and apart to clean it thoroughly and wow what a difference. It runs better than it ever. Love the WF!
01-07-2012 07:48 AM
robbiecc
Quote:
Originally Posted by sppacnivek View Post
The cam position sensor could be the culprit if there is no spark. Hope this helps.
when mine went out it did throw a code. have you hooked up a code reader just for grinns-ya never know.
01-07-2012 06:46 AM
BigGreen98 Thanks for all the help. I'm going back up there with a mechanic and diagnostic computer and wiring schematic and I'm not leaving till its fixed....... I hope lol
01-07-2012 02:01 AM
cthies guys there could be two jeeps here with the same, or similiar, problem.

http://www.wranglerforum.com/f5/new-...-120852-4.html

my 100+ thread has many ideas.....still not wprking but feel ivam near solution....

i believe my prob is goijng to be ground related.....just not sure where the groind is
01-07-2012 01:48 AM
sppacnivek Ok, remember how I told you to bypass your fuel pump relay? You can bypass your ASD relay the exact same way. The CPS(crankshaft position sensor) is less than $20, so I'd replace that if she don't start by bypassing ASD relay. If after doing those two tests she still refuses to start, I'd have someone with a diagnostic computer to check the PCM. If she's getting fuel and air, the only thing left is spark. The way Chrysler made the plug wire system makes it very difficult to check for spark. I guess one could run a bare wire from the plug boot to a timing light to check for spark. There are three things that an internal combustion engine require: correct fuel/air mixture, and correct timing of the spark. Get those three things right and she should run. The cam position sensor could be the culprit if there is no spark. Hope this helps.
01-06-2012 02:42 PM
BigGreen98 I just didn't know which slot to put power on to bypas it
01-06-2012 01:10 PM
freeskier
Quote:
Originally Posted by BigGreen98
Ok but how do I bypass the asd relay. I feel like such a tard right now because I work on cars all the time but I'm chasing my tail on such a small problem
Find the ASD relay (I would assume it is in the PDC) and jump the power.
01-06-2012 12:08 PM
BigGreen98 Ok but how do I bypass the asd relay. I feel like such a tard right now because I work on cars all the time but I'm chasing my tail on such a small problem
01-02-2012 01:35 PM
Jerry Bransford
Quote:
Originally Posted by sppacnivek View Post
This is why Ithink if you bypass ADS relay and it starts, it would be the CPS( crankshaft position sensor). If it don't start, have the PCM checked. Just saying what I would do.
A bad CPS would prevent the engine from starting. It will also prevent the ASD relay from engaging but if you bypass the ASD relay, a bad CPS will still prevent the engine from starting. The CPS is what provides the engine's master timing signal which is required for the ignition system to generate spark. Bad CPS = no spark.
01-02-2012 10:35 AM
sppacnivek This is an exert from my Jeep manual: OPERATION - PCM OUTPUT
The ASD relay supplies battery voltage (12+ volts)
to the fuel injectors and ignition coil(s). With certain
emissions packages it also supplies 12–volts to the
oxygen sensor heating elements.
The ground circuit for the coil within the ASD
relay is controlled by the Powertrain Control Module
(PCM). The PCM operates the ASD relay by switching
its ground circuit on and off.
The ASD relay will be shut–down, meaning the
12–volt power supply to the ASD relay will be de-activated
by the PCM if:
˛ the ignition key is left in the ON position. This
is if the engine has not been running for approximately
1.8 seconds.
˛ there is a crankshaft position sensor signal to
the PCM that is lower than pre-determined values.
This is why Ithink if you bypass ADS relay and it starts, it would be the CPS( crankshaft position sensor). If it don't start, have the PCM checked. Just saying what I would do.
12-31-2011 05:52 PM
Jerry Bransford Without input from the CPS, the PCM won't let the engine start period.
12-31-2011 05:33 PM
BigGreen98 Yea I swapped around all the relays and all are fine. I was under the assumption that the cam and crank sensors only controll timing of fuel and spark..... Which makes me think computer, but I don't wanna piss away 200 bucks on the computer and that not be the problem
12-31-2011 10:04 AM
Jerry Bransford
Quote:
Originally Posted by BigGreen98 View Post
I bypassed the relay and the pump works. What does this mean
That doesn't really tell you much at all. The fuel pump relay is under control of the ASD (auto shut down) relay which is under control of the PCM (engine computer) and the PCM will only energize the ASD relay when the PCM is happy with all its various inputs, especially from the Crankshaft Position Sensor and, secondarily, camshaft position sensor.

At the least, you can swap the fuel pump relay with another relay like the horn relay to verifiy you don't just have a bad fuel pump relay. There are probably 3-4 relays inside the PDC that are the same that can be swapped around for troubleshooting purposes.
12-31-2011 01:42 AM
sppacnivek Try bypassing the asd (auto shut down) relay and see if it starts. If it does, there are several possibilities. I would have to check the manual to advise on what activates the ASD. If it dont start, the ecm would be my next guess. Hope this helps.
12-30-2011 11:00 AM
BigGreen98 I bypassed the relay and the pump works. What does this mean
12-27-2011 08:40 PM
BigGreen98 No codes... Thanks for the input..... I will give that a shot
12-24-2011 10:41 AM
sppacnivek Well Big Green, I'd start by swapping the fuel pump relay with a known good relay, say the horn or hvac relay(make sure the horn or a/c works). Or test your relay, BACKINBLACK's Grand Prix electrical modificationsRelays.htm. To check fuel pump, disconnect fuel line at rail,(position in safe direction) jump a 12+ wire (preferably with a momentary push button in line) from the battery to fuel pump relay slot 87 located in the fuse box(power distribution center) on fender under hood.. This should bypass everything to send voltage to pump. If pump does not pump gas, it's the culprit. If it works I'd check the ASD(auto shutdown) relay. Any codes? I hope this helps.
12-23-2011 07:03 AM
BigGreen98 Mine did the same thing but my pump won't cycle in at all. My fuses are good but there isn't power getting to the pump.... Suggestions?
12-12-2011 11:23 PM
sppacnivek Well. Turns out the fuel pump quit pumping even though the pump motor did not fail. New fuel pump and all seems well. Thanks for the suggestions. Hope this thread helps someone else.
12-10-2011 12:51 PM
robbiecc
Quote:
Originally Posted by Jerry Bransford View Post
That the fuel pump cycles on for its normal 3 seconds when you turn the ignition switch on leads me to believe it's not the fuel pump. That you have replaced your crankshaft position sensor without it helping leads me to suspect the camshaft position sensor, on the passenger side of the engine block, on top of the shaft that used to hold the distributor.
and if the noodle heads at the parts store can't locate it on the computer, try ignition sensor--also when i replaces mine there were more than 1-difference being the connector so if you can take the old one with you it may save you a trip(wish i wouls have known)
mine would turn over good but nothing-did get a CEL though.
12-10-2011 12:25 PM
Jerry Bransford That the fuel pump cycles on for its normal 3 seconds when you turn the ignition switch on leads me to believe it's not the fuel pump. That you have replaced your crankshaft position sensor without it helping leads me to suspect the camshaft position sensor, on the passenger side of the engine block, on top of the shaft that used to hold the distributor.
12-10-2011 12:11 PM
sppacnivek Well, no fuel to injectors leads me to replace the fuel pump this fine Sat. Just never had an electric pump quit pumping all at once while not running.
12-08-2011 08:31 AM
sppacnivek I replaced CPS last night, still no start. Removed neg battery cable, replaced this morning, still no start. I poured some gas into air intake, she started right up. I just don't know if the injectors are working or the gas was entering the intake valves. I do know the ignition system is not at fault. I don't have the adapter nor the special tool to remove fuel line, as of yet. Does Jeep have a security system like GM. Had an S10 ignition security switch do this to me. Same symptoms.
12-08-2011 07:33 AM
yoopone Been through this before. I would definitly replace the crank sensor. Cheap enough part and not too hard to get too. Went to the Hardware store, all was well, turned the Jeep off, came back out and no start. Same symptoms.
12-08-2011 07:25 AM
sppacnivek Not that easy, 05 has some kind of a coil pack rail. No plug wires, looks like boots are an integral part of rail. Remove one, remove all.
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