88wagoneerXJ
NAXJA Forum User
my 88 has a new issue where it idles at 100rpm sputtering and won't rev at all in any gear P,N,D,3,L2. However put it in reverse and it's perfectly fine.
Is this the ecu? Thanks!
Is this the ecu? Thanks!
Will only run in reverse
- Thread starter 88wagoneerXJ
- Start date
- Location
- In a strange land
I wonder if the NSS could create such a situation.
I assume the Renix systems have some sort of NSS such as the H.O. systems. Is it something which can be taken apart and cleaned like the H.O. ones?
I assume the Renix systems have some sort of NSS such as the H.O. systems. Is it something which can be taken apart and cleaned like the H.O. ones?
88wagoneerXJ
NAXJA Forum User
Yes it does and has been cleaned and greased. No change. any other ideas? This is a strange one. Swapped the tcu and same issue as well. rather not have to buy another ecu but if I have to i guess I will just to rule it out. Just seems weird how it runs and revs fine only in reverse. There must be something I'm not thinking of.
lawsoncl
NAXJA Forum User
- Location
- North Idaho
I can't picture how the NSS would make it sputter.
Long shot here - Are the bellhousing-to-engine bolts tight? No visible gap? You sometimes see the bolts backed out if the trans has been previously removed, but the symptoms are usually backwards with it stalling in reverse. I would also wiggle with wiring harness along the fuel rail, especially where it crosses over to the firewall as that can flex and fray internally if the motor mounts are shot.
Long shot here - Are the bellhousing-to-engine bolts tight? No visible gap? You sometimes see the bolts backed out if the trans has been previously removed, but the symptoms are usually backwards with it stalling in reverse. I would also wiggle with wiring harness along the fuel rail, especially where it crosses over to the firewall as that can flex and fray internally if the motor mounts are shot.
Not as familiar with the RENIX era auto trans. I'd pull the plug to the TCU, or there is a fuse for the trans you can pull. See how it drives. You will have to shift manually. Also, be aware, the trans will not self brake. So, you will have to shift at appropriate RPMs.
There are about 5 items that control the transmission. ECU, TCU, TPS, NSS, and the brake light switch. I'd include the shift solenoids and speed sensor. I might suspect the TPS in this case. Also, check that the NSS is clocked right.
There are about 5 items that control the transmission. ECU, TCU, TPS, NSS, and the brake light switch. I'd include the shift solenoids and speed sensor. I might suspect the TPS in this case. Also, check that the NSS is clocked right.
