BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
yes i checked with fuel and it tried to fire as stated before. plugs are dry
-
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89 got wet now wont start
- Thread starter BenDiesel
- Start date
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
ok so i piked up a noid light kit and a efi fuel pressure kit. i have 35 psi at fuel rail while cranking and no light on the noid. i have a computer that verifys good out of a 88 im going to try see what happens.
djgrayxj
NAXJA Forum User
- Location
- West Covina
Before you condemn your existing ECU you might try this, unplug and replug in each of the two connectors.
Do the 24 pin [smaller of the two] several times, it is the on that’s transmit all of the information from the ECU to the injectors.
I believe it was 5-90 that posted that almost all ECU replacements were more likely caused by bad connections between the plugs and the ECU. But when the connectors were shoved onto the replacement ECU a good connection was reestablished, problem was solved and old ECU was blamed.
Alco check out this post
Another No start Renix issue
http://www.naxja.org/forum/showthread.php?t=999978
OP by 1985xjlaredo:
1988 Chief 5 speed OK so I have fuel at the rail. I have spark at all of the plugs. The injectors are not squirting.
8Mud posted: #12
Most likely low fuel pressure, but If your fuel pressure checks out OK. Ohms test the injector ground. Wiggle the harness around where it bends at the firewall. It can have good continuity and still be bad. The wire under the insulation where the harness makes it's bend at the fire wall can fatigue through most of the copper wires/threads under the insulation. It can ohm test OK and still not pass enough amperage to fire the injectors. There is also a ground splice farther up the harness after the bend under the tape that has given me grief.
Do the 24 pin [smaller of the two] several times, it is the on that’s transmit all of the information from the ECU to the injectors.
I believe it was 5-90 that posted that almost all ECU replacements were more likely caused by bad connections between the plugs and the ECU. But when the connectors were shoved onto the replacement ECU a good connection was reestablished, problem was solved and old ECU was blamed.
Alco check out this post
Another No start Renix issue
http://www.naxja.org/forum/showthread.php?t=999978OP by 1985xjlaredo:
1988 Chief 5 speed OK so I have fuel at the rail. I have spark at all of the plugs. The injectors are not squirting.
8Mud posted: #12
Most likely low fuel pressure, but If your fuel pressure checks out OK. Ohms test the injector ground. Wiggle the harness around where it bends at the firewall. It can have good continuity and still be bad. The wire under the insulation where the harness makes it's bend at the fire wall can fatigue through most of the copper wires/threads under the insulation. It can ohm test OK and still not pass enough amperage to fire the injectors. There is also a ground splice farther up the harness after the bend under the tape that has given me grief.
old_man
NAXJA Forum User
- Location
- Loveland, Colorado
I think your year model still had the C101 connector mounted on the firewall above the brake booster. It is notorious for getting crappy. There was a TSB that recommended removing it and wiring across the connector.
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
so the c101 was a 87 88 thing only. my jeep is a 89.
did some probing pulled the computer no corosion at the terminals. but it seems the b7 pin is the bat + and has no power. it gets bout 1 volt max while cranking for some reason but bounces around.
figured out what it was. it was the b-latch relay. engine fired so now i got to put every thing back to geather.
did some probing pulled the computer no corosion at the terminals. but it seems the b7 pin is the bat + and has no power. it gets bout 1 volt max while cranking for some reason but bounces around.
figured out what it was. it was the b-latch relay. engine fired so now i got to put every thing back to geather.
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
Guess I spoke to soon. Its gone from a no start to a start no run senario
djgrayxj
NAXJA Forum User
- Location
- West Covina
Did you bypass the whitish ceramic fuel pump ballast resistor?
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
yes i bypas the balast resistor.
it seems as soon as i let off the ignition the jeep dies. it will start and run as long as i hold the switch to start mode.
went to a few auto parts stoors and the dealer. no one has listing for the relays. can i use the 5 pin relay used in most headlight upgrades?
it seems as soon as i let off the ignition the jeep dies. it will start and run as long as i hold the switch to start mode.
went to a few auto parts stoors and the dealer. no one has listing for the relays. can i use the 5 pin relay used in most headlight upgrades?
djgrayxj
NAXJA Forum User
- Location
- West Covina
How to test relays: From Shorty
http://www.naxja.org/forum/showthread.php?t=1006312
I have had great luck using a 9v battery between 85 and 86 while checking for continuity between 30 and 87. Use the continuity check feature on your DVOM with the tone feature (assuming yours has it) on 30 and 87 and touch the battery to 85 and 86. The tone should sound and the relay should click each time you touch the battery. This test will work with the battery + on 85 or - on 85 as long as you're not trying to check a diode suppressed relay (which I don't think you'll find on any of these Jeeps) It takes fourteen hands and some luck to hold it all, but it's really easy once you get the hang of it.
Understanding Relays (Operation & Testing) By Kevin R. Sullivan
http://www.autoshop101.com/trainmodules/relays/101.html
NAPAPart Number: ECH AR201
# Relay Terminals: 5
Features and Benefits:
N.O. Terminals 30-87 @ 50 Amp
N.C. Terminals 30-87a @ 20 Amp
Coil Terminals 85-86
Or
Part Number: ECH AR272
Shorty http://www.naxja.org/forum/showthread.php?t=1006312
I have had great luck using a 9v battery between 85 and 86 while checking for continuity between 30 and 87. Use the continuity check feature on your DVOM with the tone feature (assuming yours has it) on 30 and 87 and touch the battery to 85 and 86. The tone should sound and the relay should click each time you touch the battery. This test will work with the battery + on 85 or - on 85 as long as you're not trying to check a diode suppressed relay (which I don't think you'll find on any of these Jeeps) It takes fourteen hands and some luck to hold it all, but it's really easy once you get the hang of it.
Understanding Relays (Operation & Testing) By Kevin R. Sullivan
http://www.autoshop101.com/trainmodules/relays/101.html
NAPAPart Number: ECH AR201
# Relay Terminals: 5
Features and Benefits:
N.O. Terminals 30-87 @ 50 Amp
N.C. Terminals 30-87a @ 20 Amp
Coil Terminals 85-86
Or
Part Number: ECH AR272
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
So when I let off the key after it gets started the power gets turned off to the computer. Is that the switxh or a relay some were or what?
BigSky89XJ
NAXJA Forum User
- Location
- Billings, MT
I would remove, clean, and reattach all three grounds under the hood. Renix Jeeps are extremely ground sensitive. Also try pulling the coil and ignition module and cleaning the two posts that clip in the coil. I cleaned both posts and used OxGard to stop corrosion and facilitate a better conection. The OxGard also helps repel moisture on the connection. When I first got my '89 XJ I had an issue with intermittent spark and the tachometer did not work. My problem was the wire connection to the ignition module. The group of wires that ran by the module had pressed against the female connection of the module causing the wires to pull out of the plug. Once I repaired that female plug-in I no longer had an issue and the tachometer began working. Believe me I was at the end of my rope until I tried that repair.
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
well after much headache i found the problem and it wasnt fuel related(told you so)
it was the wire that feeds power to the computer. when it was in crank mode it was back feeding power though one of the relays for some reason. and when i let off the switch it would loose power. after some reserch in the fsm i have i found that it gets its power directly from a wire under the hood attached to the power terminal on the start relay. and for some reason the wire between the lug and the fuse link was broken. i striped the wires and twisted them to gether and presto bamo started and ran like there was never a problem.
this just spurs me to want to do the ho fuse/relay box swap even more. and in any event im going to get aaa on payday
it was the wire that feeds power to the computer. when it was in crank mode it was back feeding power though one of the relays for some reason. and when i let off the switch it would loose power. after some reserch in the fsm i have i found that it gets its power directly from a wire under the hood attached to the power terminal on the start relay. and for some reason the wire between the lug and the fuse link was broken. i striped the wires and twisted them to gether and presto bamo started and ran like there was never a problem.
this just spurs me to want to do the ho fuse/relay box swap even more. and in any event im going to get aaa on payday
Alaskan89XJ
NAXJA Forum User
- Location
- Alaska
Thanks for the info. Been following your issue, as I do for any RENIX issues, lol. 1) what is 'aaa', and 2) why the upgrade(?) to HO fuse/relay box.., is that like a way better mod? Why?
Thanks
Thanks
BenDiesel
NAXJA Forum User
- Location
- lynnwood washington
aaa also known as triple a
the box is a sealed unit and has the big style fuses instead of fuse link the renix has its relays sittin in the elements getting wet
the box is a sealed unit and has the big style fuses instead of fuse link the renix has its relays sittin in the elements getting wet
