University Auto Repair Flagstaff - recommend (1 Viewer)

This site may earn a commission from merchant affiliate
links, including eBay, Amazon, Skimlinks, and others.

Joined
Jan 9, 2011
Threads
43
Messages
1,010
Location
Flagstaff, AZ
University Auto Repair in Flagstaff diagnosed and resolved a mysterious cold rough idle and stumble that disappeared once the engine warmed.

Flagstaff's Toyota dealership thrice tried and failed, and then gave up. A few other shops wouldn't even touch this vintage (94 1FZ-FE). The truck's service history suggests that previous owners had chased the problem with other shops for years.

I asked the guys at University Auto Repair to take whatever time they need to figure it out. They worked through a methodical diagnosis and figured it out, and for a reasonable price.
 
Three interacting problems; faulty splice on cylinder 6 injector wiring; faulty wire connections on cylinder 4 and 5 injectors; clogged egr line. Because the problem resolved once the engine warmed, I was worried it was head gasket or cracked head (resealing once the metal expanded), unmetered air, or a leak into the exhaust upstream of the O2 sensors causing a too-rich mixture that'd lean out upon warming. I was, as usual, wrong, as were many others.
 
Last edited:
Three interacting problems; faulty splice on cylinder 6 injector wiring; faulty wire connections on cylinder 4 and 5 injectors; clogged egr line. Because the problem resolved once the engine warmed, I was worried it was head gasket or cracked head (resealing once the metal expanded), unmetered air, or a leak into the exhaust upstream of the O2 sensors causing a too-rich mixture that'd lean out upon warming. I was, as usual, wrong, as were many others.

Thats a pretty common problem on the 93-94's. Did they wrap the wiring harness with insulating tape near the EGR tube after the repair? If not, I have some left over wrap from when I did mine.
 
Thats a pretty common problem on the 93-94's. Did they wrap the wiring harness with insulating tape near the EGR tube after the repair? If not, I have some left over wrap from when I did mine.

I remember having some idle issues that I was able to solve by replacing my EGR stuff but haven't heard of the electrical stuff potentially causing problems... I'm gonna have to look into that for some preventative maintenance.
 
Thats a pretty common problem on the 93-94's. Did they wrap the wiring harness with insulating tape near the EGR tube after the repair? If not, I have some left over wrap from when I did mine.
Thanks man. I might take you up on that.
 
wiring harness by the EGR tube can be pulled away from it with a zip tie - Kevin (Tools R Us) did this on EVERY single 80 that came by the shop, for free - while he was casually chatting with the owner :lol:
 
wiring harness by the EGR tube can be pulled away from it with a zip tie - Kevin (Tools R Us) did this on EVERY single 80 that came by the shop, for free - while he was casually chatting with the owner :lol:

Yep. I checked and University both insulated and zip-tied the wiring away from the EGR tube. So, more high marks. Hopefully that ends my learning experience with this particular quirk of the 94s.
 
it's not just the '94s, all 80 series have that "wiring-harness-too-close-to-the-EGR-tube" problem
 
it's not just the '94s, all 80 series have that "wiring-harness-too-close-to-the-EGR-tube" problem
The 95+ are 2-3” further away from the egr pipe than the 93/94. No reason not to wrap them on the later model, but they have plenty of clearance compared to the 93/94.
 
Yep. I checked and University both insulated and zip-tied the wiring away from the EGR tube. So, more high marks. Hopefully that ends my learning experience with this particular quirk of the 94s.
My guess would be the guy who worked on your truck has or had an 80… lol
 

Users who are viewing this thread

Back
Top Bottom