• Welcome to the new NAXJA Forum! If your password does not work, please use "Forgot your password?" link on the log-in page. Please feel free to reach out to [email protected] if we can provide any assistance.

88 crank no start

buzzbombxj

buzzbombxj

NAXJA Forum User
Location
lake chabot
My 88 with the 4L will crank over but not start, just like the cps or ckps is out. It has been doing this for almost a year now, steadily getting worse, but after I replaced to cps I thought I fixed it. I can hear my fuel pump prime and there is pressure at the rail.
I have tried:
New disributer, old one was in terrible shape.
New computer, got desperate
New cap, lots of material transfer
Wires are only 8 monthes old.

I have continuity between the stator wires and the computer, and between the cps and the computer, and the coil and computer. All grounds are grounded.

I can usually get it to start, after a ten minute wait, which I spend un and re plugging in every connector on the harness. I don’t know if my unplugging and re plugging does anything really, but it leads me to suspect an electrical gremlin, recently this hasn’t even worked, and now my registration is lapsed case I can’t get it to the man to smog.

I need a fresh perspective and for sombody who knows what they area doing to make a suggestion. It’s pobably a $10 part or an easy fix, but I will do what it takes, I miss my poor jeep.
 
1. Renix--grounds. Dipstick tube--grounds for ICM, ECU, o2 sensor--CRITICAL.

2. Renix--grounds. One single ground for the entire unibody--lousy braided strap at rear of head to firewall, driver's side. Replace with 4 or 2 ga. cable, clean head and firewall to bare metal, treat with anti-corrosive material, make the connections TIGHT.

3. Renix--grounds. Add a ground from the negative battery terminal to the passenger's side fenderwell. Clean/treat/tight as in number 2.

Post back results.
 
Thanks for the help! I have an hour before work ill go check all this out before then and post back after.
 
joe_peters said:
1. Renix--grounds. Dipstick tube--grounds for ICM, ECU, o2 sensor--CRITICAL.

2. Renix--grounds. One single ground for the entire unibody--lousy braided strap at rear of head to firewall, driver's side. Replace with 4 or 2 ga. cable, clean head and firewall to bare metal, treat with anti-corrosive material, make the connections TIGHT.

3. Renix--grounds. Add a ground from the negative battery terminal to the passenger's side fenderwell. Clean/treat/tight as in number 2.

Post back results.
Click to expand...

1. Checked, said 0 ohms. A couple years ago when replacing that ground cable I stripped out the nut and so I moved the ground over one hole. Probably not an issue but worth mentioning
2. Braided cable looked old, I added 2 ga cable with crimped ends going from firewall to the intake manifold right there, the bolt was convenient, hopefully it will be fine. Tons of di-electric grease everywhere, wire brushed liberally first.
3. Same as 2, 2 ga cable crimped ends, di-electric grease over wire brushed metal.

Tried to start, battery gave up after second try, on the quick charge now. I will try later when its charged. I’m excited myself because I feel like I am making progress.

Thanks again for the help so far
 
There is a common problem with the C101 connector above the brake booster. Jeep recommended cutting it out and wiring direct.
 
Is that the one that looks like it connects two harnesses together?
 
Yes. Right near the brake booster. short of eliminating it, I have had some success with unbolting the two halves, cleaning out the tar crap and spraying with contact cleaner before reassembly.
 
cruiser54 said:
Yes. Right near the brake booster. short of eliminating it, I have had some success with unbolting the two halves, cleaning out the tar crap and spraying with contact cleaner before reassembly.
Click to expand...

And some dielectric grease wouldn't hurt.
 
I have dielectric grease on everything now, including that connector. Since it still wont work i will try splicing the harnesses together. Anybody else with ideas?
 
joe_peters said:
1. Renix--grounds. Dipstick tube--grounds for ICM, ECU, o2 sensor--CRITICAL.

2. Renix--grounds. One single ground for the entire unibody--lousy braided strap at rear of head to firewall, driver's side. Replace with 4 or 2 ga. cable, clean head and firewall to bare metal, treat with anti-corrosive material, make the connections TIGHT.

3. Renix--grounds. Add a ground from the negative battery terminal to the passenger's side fenderwell. Clean/treat/tight as in number 2.

Post back results.
Click to expand...

great information.

too bad it didn't help the problem.
however, it is good preventive maintenance.

BOB
 
Some updates, the jeep runs!

Well it runs once it starts, which has happened twice in the last month and a half. I am still beating my head against the wall figuratively, and soon, literally.

Have a new coil and icm, for some reason after installing the icm it worked for an afternoon. I had a beautiful afternoon driving it around, but it did not start for weeks afterwards.

So with a new distributer
ICM
Coil
Cap
Spark plug Wires

My jeep sits, sad and lonely. I’m not sure what my plan is now, but I think I’m going to do some more disassembly then reassembly, that seems to work for most other things. This is not my happiest post ever.
 
When it does not start .... have you confirmed whether or not you are getting spark?
If you are getting spark (confirm with a inline checker) then it could be your injectors (confirm with a noid light).
 
I ordered this in-line checker; http://www.napaautoparts.com/Search/Detail.aspx?R=SME705950_0238939836
Then went on a five day boat camping trip to lake Sonoma, good times.
Back in town and back to work, today I tried my new toy. The jeep started mysteriously the first time, idled for about ten minutes, then died. It was a good time to try my tester. I tried the coil wire, and a few plug wires. 80% of the time there was no spark, 15% of the time there was, and 5% of the time there was spark that grounded though my arm to the fender :D
Every time that I saw the light going off on the tester the jeep started, and (this seems crazy) it seems like my jeep is more likely to start with the tester inline than normal. Maybe there is something crappy about my AutoZone plug wires?
So yeah, spark is an issue still.

On a side note, I have actually been wondering about the injectors. They haven't been replaced in the 6 years I have had the jeep. What made me think of it is the slightly rough idle that is still there when it runs.
 
remove the fuel pump, I had a very similar problem and it ended up being the fuel line between the pump and the sender, it was not holding the pressure......
 
You must log in or register to reply here.

Similar threads

D
1996 4.0 No Crank, Starter Works When Jumped
Replies
10
Views
176
DirtySouthXJ
D
J
Cranks, Fires, Dies - 1991 Briarwood Restoration
Replies
17
Views
3K
Jam Master Jay
J
Xtreme XJ
Crank, no start even with new CPS...
Replies
13
Views
2K
Xtreme XJ
Xtreme XJ
WGxj
1997 XJ 4.0L AW4 Long Crank Problem
Replies
5
Views
73
Tim_MN
Tim_MN
J
Sudden Crank/No Start condition - also no accessories in On/Run?
2
Replies
22
Views
3K
RCP Phx
R
Back
Top