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Fuel Injected 1981 TR7 Rough Idle/ Surging

Posted: 05 Mar 2017 21:55
by TR7Spider
I recently took my fuel injected 1981 Triumph TR7 out of storage and it is surging from 700 to 1400 rpm after driving it for an hour. This only happens when the car is warm and has been driven for a while.

Some history about the maintenance:
Recent Oil Change, w/ new filter
New Bosch Fuel Pump, w/ new filter
New Bosch Spark Plugs, spark plug wires, distributor, and rotor
New Air Filter
Has the original fuel injectors, relay, and afm.

Any ideas on what's wrong? Do you think it could be something with the timing, alternator, AFM, thermotime switch, secondary air valve, relay, fuel injectors, or the ecu?? Has anyone had something similar happen?

Here's a video of it happening after being warmed up...

https://www.youtube.com/watch?v=q9PjqsTOHOM&feature=youtu.be

Re: Fuel Injected 1981 TR7 Rough Idle/ Surging

Posted: 06 Mar 2017 01:46
by FI Spyder
Air leak after the air mass meter? I would check the condition of the hose for cracks/bad connections like the one going to the aux air valve etc. I replaced all mine as a mater of course when I got my car (except the big hoses from air plenum to intake).

Although I never done some have pried of the cover o the AFM to clean the slide conacts of the flapper. I'd consider that one of the last things.

The big air hose is fabric supported by wire and can be worn through. Mine wasn't too bad but I wound black duct tape at an angle to get double coverage as a precaution and wound braided string that I got from craft store around to replace frayed dirty original for looks. A guy wanted to know where I bought a new hose from.

Image

Re: Fuel Injected 1981 TR7 Rough Idle/ Surging

Posted: 06 Mar 2017 18:16
by HDRider
I had the same issues with my 1981 PI Tr7. It was holes in the hoses between the Air-mass meter and the throttle.

Silicone replacement hoses are available at

http://www.autosiliconehoses.com/silico ... etres.html

Edward Hamer
Petaluma CA