Hey all, I've had an issue with my 91 fj80 starting readily but dying in a few seconds. I pulled the throttle body to inspect and test the tps. I was having trouble getting the tips reinstalled and engaging the tabs on the throttle body with the slots on the tps without having the throttle partially open. I compared my existing t.b. to an old one I had laying around this is what I found. T.b on the right is the old one. Old t.b to tps engagement is horizontal (when installed) current t.b. to tps is vertical. What's going on, and which is correct?
TPS fixed. Questions about ISC and starting easy but dies after a few seconds update
- Thread starter crzrcrzy
- Start date
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The Throttle link assembly (where the cables attach) appear to be roughly in the same position for both TB's but the TPS levers are not.
What position (s) are the individual butterfly valves (plates) at rest, is one open and the other partially open or both closed?
Do both butterfly plates both move freely ie; can you turn the butterfly plate easily by hand, same amount of movement between both, do both snap back under spring tension, to fully closed or??
Are the levers (which appear off by ~90 degrees) tight on both?
Do either of those levers move independently of the butterfly plate or Throttle link assembly ie loose/wobbly??
More photos would help
What position (s) are the individual butterfly valves (plates) at rest, is one open and the other partially open or both closed?
Do both butterfly plates both move freely ie; can you turn the butterfly plate easily by hand, same amount of movement between both, do both snap back under spring tension, to fully closed or??
Are the levers (which appear off by ~90 degrees) tight on both?
Do either of those levers move independently of the butterfly plate or Throttle link assembly ie loose/wobbly??
More photos would help
Last edited:
- Thread starter
- #4
Everything is as it should be. 100% operable. The only difference is the orientation of the levers that the tps engages. I think Godwin is correct. The orientation is different from the 88 (fj62) and the 91 (fj80). It definitely threw me for a loop. I had swapped out the original tps from the fj80 with the one from my parts throttle body not knowing there was a difference. Got the correct tps ordered. Hope it fixes the issue.
Sounds like an AFM issue or torn intake hose shutting down the fuel pump.
Have you tried bypassing the fuel pump logic by jumping pins 1-8 in the diagnostic connector on the firewall?
- Thread starter
- #7
Update: new tps installed and working properly. I did jump pins FP-B+, didn't seem to have any affect. Pulled and checked the ISC and it seems to function as it should. However, I had pulled the EFI main relay to clear codes and had left the ISC unplugged. After reinstalling the EFI relay I left the ISC unplugged and she fired right up as usual but held idle around 850rpms. I then plugged the ISC back in while she was running. No effect. Shut her down and when I started her back up same issue, start then slowly drop idle and die. No leaks in the intake or vacuum lines. Any other suggestions. I'm at a loss.
Pulling the EFI RELAY will NOT clear codes or reset the ECU.
To clear codes and reset the ECU, you need to pull the 15 amp EFI FUSE or disconnect the battery.