Renix Disaster
#76
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Year: 1990
Model: Cherokee (XJ)
Engine: 4.0
#79
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Year: 1988
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I have finally got back out there to check the jeep again and 20 minutes later I am ready to order parts again. I disconnected the fuel pump and the short went away so that means that it must be in that component. I really wish that it hadn't of done that. I have been replacing so many parts that i "thought" could be the issue with no luck. I would rather find the obvious problem and go from there.
I had a full tank of gas, so it needed to be pumped out so the pump could be removed. Thing is, the pump worked great. How could it be shorted and still pump out 15 gallons of gas? Here I go again second guessing this bad part. Does anyone have a normal reading of this? Does the pump shunt to ground when it is not being used?
I had a full tank of gas, so it needed to be pumped out so the pump could be removed. Thing is, the pump worked great. How could it be shorted and still pump out 15 gallons of gas? Here I go again second guessing this bad part. Does anyone have a normal reading of this? Does the pump shunt to ground when it is not being used?
#80
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How did you run the pump to empty the tank?
And no, it doesn't shunt to ground ever.
And no, it doesn't shunt to ground ever.
#81
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I pulled the supply hose from the back of the filter and put it into a portable gas tank. When I jumped the fuel pump relay it pumped fuel into the portable tank.
When i got the fuel pump out i metered the windings and got two ohms. Everything there is fine. So in the end my mystery short was just the resistance of the fuel pump windings.
Now I am back to nothing. Any ideas?
When i got the fuel pump out i metered the windings and got two ohms. Everything there is fine. So in the end my mystery short was just the resistance of the fuel pump windings.
Now I am back to nothing. Any ideas?
#82
No, I don't lick fish.
Sorry if this was already mentioned but, have you tried bypassing the fuel pump ballast resistor?
#83
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#84
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Give up
I have come to the point where I don't want to work on it anymore. I am going to put everything back together and take it to a shop and see what they can do with it. I figure that because I am in California and it is a minimum of $100/hour, there wont be any upgrades anytime soon. Anyone recommend any mechanics in the Petaluma/Santa Rosa California area?
#85
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I wish you luck. I would try to find a mechanic the specializes in Jeep vehicles as most today were born after OBD1 started and won't have equipment to diagnose anything from the Renix era. If they work on it for more than a day, you will surpass the value of the vehicle in what they want to charge.
Perhaps there's a Jeep group that meets in your area and they could recommend someone.
I took mine to a Chrysler dealer once and he told me they got rid of their DRB tools years ago.
Perhaps there's a Jeep group that meets in your area and they could recommend someone.
I took mine to a Chrysler dealer once and he told me they got rid of their DRB tools years ago.
#86
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Year: 1988
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There is a Jeep shop (Jeep Speed Shop) in the area where I live so I took it there.Iit has been there for about three weeks and they finally got time to work on it Wednesday.
They are as stumped as I was (we were), I just hope their experience is enough to find the problem. As I mentioned earlier in this thread, when you turn the key off there is, sometimes, a kick where one cylinder will fire one time. That seems to be what is most interesting to the mechanic and he is trying to trace that down. He told me he had one guy shorting the starter and he played with the Key lock to try to find the "Sweet Spot" where the engine would run. He did not find that spot. No that I have had time to ponder the issue I wonder if it is maybe the drop in voltage that makes the computer want to fire? Any ideas out there?
When I noticed this issue I replaced the ignition switch and eventually got bored and went back to troubleshooting the no spark rather than the intermittent spark.
He also has an OBDI reader for this Jeep and it tells him that the ECU is not getting power. I checked power at the ECU and I know that the 12V signal is there.
I go in to check on it once a week to see what progress has been made. I will try to post again next week, if there has been any progress.
They are as stumped as I was (we were), I just hope their experience is enough to find the problem. As I mentioned earlier in this thread, when you turn the key off there is, sometimes, a kick where one cylinder will fire one time. That seems to be what is most interesting to the mechanic and he is trying to trace that down. He told me he had one guy shorting the starter and he played with the Key lock to try to find the "Sweet Spot" where the engine would run. He did not find that spot. No that I have had time to ponder the issue I wonder if it is maybe the drop in voltage that makes the computer want to fire? Any ideas out there?
When I noticed this issue I replaced the ignition switch and eventually got bored and went back to troubleshooting the no spark rather than the intermittent spark.
He also has an OBDI reader for this Jeep and it tells him that the ECU is not getting power. I checked power at the ECU and I know that the 12V signal is there.
I go in to check on it once a week to see what progress has been made. I will try to post again next week, if there has been any progress.
#87
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Year: 1988
Model: Cherokee
Engine: 4.0L
Dont listen to Cruiser. He is a senile old gas huffer. He doesnt even own a Jeep, its just an old Chevy Blazer with Jeep emblems glued on. Did you know his real name isnt even Cruiser?!
All kidding aside I will regale you with a story of how he coached me out of a no start situation,and perhaps there is a grain of wisdom that may applied to your situation We were in some town in Ohio on the banks of Lake Erie, not too far from the Jeep factory in Toledo. We stopped to grab two McSomethings and parked while we scarfed them. I went to go start the car and it just kept cranking, so we decided to get a hotel for the night and I called cruiser probably crying like a man baby. We first thought that it was the fuel pump, so I replaced it with a brand new Bosch. No change. The hotel was booked for the next few nights so we had to get going. I was getting frustrated and feeling the pressure of my situation, but Cruiser reassured me I was doing well and almost there. I didnt believe him but pressed on anyway. Next he told me to look at my relays. I got in there while my wife cranked the engine. Unfortunately I got the **** shocked out of me, but fortunately I noticed something. The plug wire from the coil to the cap was cracked and electrical current was arcing off to my coolant overflow hose. The local napa didnt have them in stock, so I took some electric tape, wrapped it up, and Uncle Jess roared back to life instantly.
My recommendation if you havent done so already is search high and low for any bad grounds or other electrical vampires. Cruiser has not only taught many of us to fix our Renix's, but for me most importantly, to enjoy the challenge and reward of the process itself. Also if you havent done so already and you are swapping ECU's,pop in a 428 or 429 from a 89-90 XJ/MJ. Makes a big overall difference. Ill shut up now as this fire that I am sitting next to is dying down, making me feel much less like Mark ****in Twain.
All kidding aside I will regale you with a story of how he coached me out of a no start situation,and perhaps there is a grain of wisdom that may applied to your situation We were in some town in Ohio on the banks of Lake Erie, not too far from the Jeep factory in Toledo. We stopped to grab two McSomethings and parked while we scarfed them. I went to go start the car and it just kept cranking, so we decided to get a hotel for the night and I called cruiser probably crying like a man baby. We first thought that it was the fuel pump, so I replaced it with a brand new Bosch. No change. The hotel was booked for the next few nights so we had to get going. I was getting frustrated and feeling the pressure of my situation, but Cruiser reassured me I was doing well and almost there. I didnt believe him but pressed on anyway. Next he told me to look at my relays. I got in there while my wife cranked the engine. Unfortunately I got the **** shocked out of me, but fortunately I noticed something. The plug wire from the coil to the cap was cracked and electrical current was arcing off to my coolant overflow hose. The local napa didnt have them in stock, so I took some electric tape, wrapped it up, and Uncle Jess roared back to life instantly.
My recommendation if you havent done so already is search high and low for any bad grounds or other electrical vampires. Cruiser has not only taught many of us to fix our Renix's, but for me most importantly, to enjoy the challenge and reward of the process itself. Also if you havent done so already and you are swapping ECU's,pop in a 428 or 429 from a 89-90 XJ/MJ. Makes a big overall difference. Ill shut up now as this fire that I am sitting next to is dying down, making me feel much less like Mark ****in Twain.
Last edited by cruiser54; 10-21-2017 at 08:35 AM.
#88
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Year: 1990
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Yeah, I remember those whiny *** calls....
You should probably enlighten the crowd on how we met in person.
You should probably enlighten the crowd on how we met in person.
#89
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Cruiser did help me work out some grounding issues but unfortunately we were not able to get it running. I am sure if he had it right in front of him he would be able to find the issue. I just got tired of being frustrated so I took it to a shop, let them be frustrated for a while.
Cool story tho
Cool story tho
#90
Senior Member
He told me he had one guy shorting the starter and he played with the Key lock to try to find the "Sweet Spot" where the engine would run. He did not find that spot. No that I have had time to ponder the issue I wonder if it is maybe the drop in voltage that makes the computer want to fire? Any ideas out there?
He also has an OBDI reader for this Jeep and it tells him that the ECU is not getting power. I checked power at the ECU and I know that the 12V signal is there.
I go in to check on it once a week to see what progress has been made. I will try to post again next week, if there has been any progress.
He also has an OBDI reader for this Jeep and it tells him that the ECU is not getting power. I checked power at the ECU and I know that the 12V signal is there.
I go in to check on it once a week to see what progress has been made. I will try to post again next week, if there has been any progress.
Last edited by 67 GMC; 10-22-2017 at 07:46 AM.