Curtis2010
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On a RENIX system??
Jeep won't start
- Thread starter Homercidal
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Help Support Homebrew Talk:
On a RENIX system??
ubnserved
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Did you replace the cap and rotor like you were going to?
I second the "smell the dip stick " there should not be any smell of gas. If you have cranked the engine many times it will have flooded the engine, fouled the plugs and washed the cylinders down (lowering compression). Recommend oil change 8f that is the case. if you check your oil regularly you may also notice that it measures more than last time you checked.
There are 2 ways to clear a flooded modern fuel injected engine. 1 (easiest) make sure battery is fully charged, get into the vehicle hold the pedal to the floor and crank until it starts firing. Holding the pedal to the floor tells the computer to put it in clear mode and will shut off the injectors and allow more air into the engine. This will usually work on fuel injected vehicles that have just been flooded. The longer the plugs have been soaking in gas the harder it is to clear. If it does not start firing in 10 to 15 seconds or there is not a noticeable improvement in the way it is cranking stop and use method 2. 2nd method: remove plugs disconnect injectors or use method above and crank engine about 10 seconds or so to clear gas from cylinders. Clean and reinstall plugs or replace with new ones. (Cleaning plugs does not always work especially if they have been soaking in gas and this can lead to frustration and tools flying inexplicably to places that they shouldn't be.)
NOTE: and I know I am repeating myself. Once plugs have been fouled not all can be cleaned and reused. Some plugs it will work fine some will not fire correctly again you can avoid frustration by just replacing them and it is always best to replace with oe plugs don't let the parts store sell you any "fancy" crap for twice the price.
Good luck
I second the "smell the dip stick " there should not be any smell of gas. If you have cranked the engine many times it will have flooded the engine, fouled the plugs and washed the cylinders down (lowering compression). Recommend oil change 8f that is the case. if you check your oil regularly you may also notice that it measures more than last time you checked.
There are 2 ways to clear a flooded modern fuel injected engine. 1 (easiest) make sure battery is fully charged, get into the vehicle hold the pedal to the floor and crank until it starts firing. Holding the pedal to the floor tells the computer to put it in clear mode and will shut off the injectors and allow more air into the engine. This will usually work on fuel injected vehicles that have just been flooded. The longer the plugs have been soaking in gas the harder it is to clear. If it does not start firing in 10 to 15 seconds or there is not a noticeable improvement in the way it is cranking stop and use method 2. 2nd method: remove plugs disconnect injectors or use method above and crank engine about 10 seconds or so to clear gas from cylinders. Clean and reinstall plugs or replace with new ones. (Cleaning plugs does not always work especially if they have been soaking in gas and this can lead to frustration and tools flying inexplicably to places that they shouldn't be.)
NOTE: and I know I am repeating myself. Once plugs have been fouled not all can be cleaned and reused. Some plugs it will work fine some will not fire correctly again you can avoid frustration by just replacing them and it is always best to replace with oe plugs don't let the parts store sell you any "fancy" crap for twice the price.
Good luck
tjpfeister
Well-Known Member
I'm not sure about the early Jeep FI engines (anything labeled "litre" and sold by AMC).But all Chrysler era products with the JTEC or newer engine controllers will either flash or display the codes on the dash.
Curtis2010
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Its my understanding that the old RENIX system does not store any codes. I've got a scanner which will save data, but if its not hooked up when the problem happens then you missed it.
For that reason I'm building an app on Arduino + Android with the objective of having it hooked up full time and logging/displaying data, because sensor issues are often intermittent and can be a bitch to catch.
There is RENIX group on Yahoo with lots of good info and a few versions of hardware/software in progress for interfacing to RENIX.
Buy a diesel powered vehicle. No more spark plug problems...
OP
OP
The code display ended at this year. I have to take it in to read them (or borrow an scan tool, which I have no line on ATM.)
I did not get a chance to do anything last night. I did plan to borrow a fuel pressure gauge from Autozone, but forgot while Xmas shopping with the girls. I did stop and buy a spark tester downtown on my way home from work. As long as the fuel pump is ok I am confident that this thing can be fixed pretty cheaply and easily.
I can't work on it much tonight as it's the wife's birthday and I have to cook and prepare for a party. If I am lucky I might get a bit of time, but I'm not counting on it. Since I have the cap and rotor I'll be putting them on and see what happens. Also check spark while doing so. I should have hooked up the battery charger this morning so it could be topped off when I get home. I might run home at lunch and do that. It's probably kind of low considering I cranked it pretty good trying to clear a flood situation.
I can also check TDC when I change the cap and test #1 plug wire. Just need to have someone there to bump the engine over.
I did not get a chance to do anything last night. I did plan to borrow a fuel pressure gauge from Autozone, but forgot while Xmas shopping with the girls. I did stop and buy a spark tester downtown on my way home from work. As long as the fuel pump is ok I am confident that this thing can be fixed pretty cheaply and easily.
I can't work on it much tonight as it's the wife's birthday and I have to cook and prepare for a party. If I am lucky I might get a bit of time, but I'm not counting on it. Since I have the cap and rotor I'll be putting them on and see what happens. Also check spark while doing so. I should have hooked up the battery charger this morning so it could be topped off when I get home. I might run home at lunch and do that. It's probably kind of low considering I cranked it pretty good trying to clear a flood situation.
I can also check TDC when I change the cap and test #1 plug wire. Just need to have someone there to bump the engine over.
The code display still works. Just cycle the key on and off three times. If no codes are present, it will either display "no code" or it'll just display the mileage. It's been a Chrysler feature since the late 80s. Still works on my '06 Ram. (Cummins diesel BTW)
tjpfeister
Well-Known Member
Right, it will work on Homer's, but may not on Curtis' since his is AMC era. Older stuff flashed the check engine light in a pattern to show codes, since digital odometers weren't always a thing.
OP
OP
Odd. I've tried several times over the years when I've actually had the LIGHT on the dash, and it just shows mileage. Then I take it in and get it read at the CarQuest store and it gives a result.
OP
OP
I was busy and never got to messing with it. I think I will try to tow/push it into the garage next day or two so I can work on it out of the weather where there is light and power after 5:00.
fuzzy2133
Well-Known Member
Homercidal sounds like you are on the right track. Do not over look your battery and cable connections. I have to harp on my guys in the shop all the time on battery voltage before they go chasing electrical issues.
Kirkwooder
Emperor of all things nobody cares about
It is likely that some where near you there is a place of business that has a large blue oval sign in front of it and a good selection of fine looking and running automobiles in the parking lot. Tow your jeep there and they will take it off your hands and help you find a good vehicle, that runs fine, for a nominal fee! 
OP
OP
It is likely that some where near you there is a place of business that has a large blue oval sign in front of it and a good selection of fine looking and running automobiles in the parking lot. Tow your jeep there and they will take it off your hands and help you find a good vehicle, that runs fine, for a nominal fee!
Yeah, we just did that recently. I'm not sure what your idea of "nominal" is, but they didn't have anything like that where we were looking!
I'm driving my wife's old durango around while I work on this. Having a spare vehicle has been nice, but is hasn't exactly lit my ass on fire to get the Jeep fixed.
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OP
Unless someone stole up in the mid of night, popped the hood and swapped some plug wires around, yes.
Kirkwooder
Emperor of all things nobody cares about
Definition of Nominal fee at any car dealership: An arm, two legs, your first and third born, and twice as much money as it should be without any of the other stuff!
Maybe Jeep's are different? I remember when Chrysler bought Jeep from AMC. It took a few years to incorporate Chrysler's computers into the Jeep line, but I thought they would have done that by 1999. I left Chrysler in 1992, so maybe they didn't.
Try it on the Durango, it should work on that. What year is the Durango?
Oh, and stay away from the blue oval, they're Found On the Road, Dead...
fuzzy2133
Well-Known Member
I have had vehicles from each of the Big 3 over the years and all you get are different headaches. I am becoming a believer in the less bells and whistles you have increases your vehicle reliability.
OP
OP
My friend had a 1996 that he could get the code from. I checked into it when I couldn't get mine to work and it looked like they ended that ability at 1998 for the Cherokee.
I haven't tried with the Durango. I did just have a light on for the system that recirculates gas fumes back into the engine. Must have had a leak from the cold. It went away a few days ago.
For what it's worth, I had a '96 Cherokee that the wife drove most of the time (I'm on my motorcycle 99% of the time) and she would park in the driveway and the next morning it wouldn't start for her. Changed the cam sensor after reading the code. I think I ended up changing the crank sensor at one point too. It had 130,000 miles on it and other than normal maintenance and a water pump those were the only sensors that I changed.
If I recall those were cheap and I think someone already stated they are high fail items.
That 4.0L motor is almost bullet proof in my experience, they should be putting that motor in more jeeps.
Now if I could get a window regulator to work on my Liberty I would be happy.
Good luck, I know it can be frustrating at times.
If I recall those were cheap and I think someone already stated they are high fail items.
That 4.0L motor is almost bullet proof in my experience, they should be putting that motor in more jeeps.
Now if I could get a window regulator to work on my Liberty I would be happy.
Good luck, I know it can be frustrating at times.
OP
OP
I had replaced the cam and crank sensors at one point not that long ago due to a rough run condition and error code. That didn't actually fix the problem. It was reseating a computer plug that fixed it.
You should be able to find a regulator for the Liberty. I've replaced them on the Jeep and Durango a few times. Pretty easy. They cost about $60 IIRC.
You should be able to find a regulator for the Liberty. I've replaced them on the Jeep and Durango a few times. Pretty easy. They cost about $60 IIRC.
Just make sure your wife knows what's bothering you
Women....
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I didn't spend as much time with it as I wanted. I did a check on one or two cylinders and the spark would not show on my test at the 20KV gap. I set for 10KV and it sparked ok, but I noticed a lot of arcing around the distributor. I removed the ground strap and cleaned and replaced (Connections all looked good) and even added a ground from teh head to the body and then to the negative battery terminal and it still arced across the distributor through the wire boots.
I'm leaning towards the plug wires, but I have not actually measured the voltage going to the coil while cranking yet. I'd consider a fuel problem but it didn't even fire when I sprayed starting fluid into the manifold. Generally you will get SOME fire condition with that stuff if there is any spark in the cylinder under compression.
Also verified distributor is pointing to 1 when cylinder 1 is TDC, so timing should not be a problem.
I'm leaning towards the plug wires, but I have not actually measured the voltage going to the coil while cranking yet. I'd consider a fuel problem but it didn't even fire when I sprayed starting fluid into the manifold. Generally you will get SOME fire condition with that stuff if there is any spark in the cylinder under compression.
Also verified distributor is pointing to 1 when cylinder 1 is TDC, so timing should not be a problem.
tjpfeister
Well-Known Member
You have got to deal with that arcing before chasing anything else. Cheers
yeah, I replaced the right rear one this past summer, now the left rear is out and the cable must have knocked the handle linkage out of wack cuz the door wont open now. My oldest has been taking it to college so I never have it long enough to look at it. Maybe if the temp is okay this weekend and if it's not raining I will get a chance to pull the door panel off and get the handle working anyway. Always something.
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OP
I had a theory that the arcing was because the engine wasn't getting a good enough ground, sending the voltage somewhere besides the plug. positively grounding the engine (head) should have absolved the ground as being the problem I think. Next step in that direction may be the plug wires? I find it hard to believe that there wasn't a misfire or noticeable loss of power before it decided to just not start, if the wires were the problem.
True that. I still find it cheaper than a car payment, and in general the Jeeps have been pretty good mechanically.
You're arcing from the coil wire at the cap? You should replace the cap, and while you're at it, change the wires too. If the electricity is escaping, it's because it's found an easier way out. Most likely a bad cap, but could be high resistance in the wires.
