Jeep XJ stumbles and stalls
For quite a while now Jenny’s 1992 Jeep Cherokee has had a stumble or hiccup while driving. We have tried changing a lot of parts to make it go away. New crank sensor, fuel pump etc.
On her last off road adventure the stalling got so bad as to be dangerous. At one point the Jeep would not go into reverse without stalling. It became very noticeable that whenever the engine shifted positions it would stall.
We checked all the wring connections that could move and they all seemed fine. We were close to ordering a new distributor.
We made one last investigation and found that moving the main harness that comes from the firewall to the engine would stall the engine. There are no connectors in this bundle so it was a bit of a surprise to find trouble in this loom.
I pulled off the cover and cut off the tape. I began pulling on individual wires to see which one caused the stumble. We soon narrowed it down to the green wire that was spliced to six others.
This turned out to be the power wires for the six injectors. The factory crimp was covered in heat shrink and looked in good condition. Even after removing the heat shrink, there was no visual indication of a problem. However tugging on the wire caused the engine to stumble or stall.
To repair, I cut out eh splice and stripped back the wires. I tinned them with solder. I added a short section of wire and soldered all seven wires to the new piece. I then covered it with tape to insulate.
The engine now runs smoother indicating that even when it was working some injectors were not always firing. So far the hiccups on the interstate are gone and there have been no stalls off road.