toyota

[leccie]

Hi still got my old corolla 1991 and never failed a test yet [some of you still laugh]
but sometimes the old girl drops revs for no apparent reason for a few moments then picks up
then runs fine diagnostics cannot find anything wrong
anyone got any SERIOUS ideas
1991 toyota corolla 1.3 GL 2E ENGINE

[HAB]

Idle air control valve probably needs either cleaned or replaced. Aerosol carb cleaner will do the trick.

IIRC the IAC valve is located under a cover in the throttle body, but I could be wrong.

[Wadeski]

does it happen when the engine is cold, warm, hot (i.e. just off the motorway), or at any time?

might be as simple as an idler pulley but could be electrical too. how far do the revs drop? does the car nearly stall?

i must say my MR2 revs sometimes drop at idle when the engine isnt warm yet, but it never stalls so i dont really worry?

[PaulGT3]

Wadeski said:

i must say my MR2 revs sometimes drop at idle when the engine isnt warm yet, but it never stalls so i dont really worry?

Most likely the cold start 5th injector needs replacing/cleaning.

[Wadeski]

tbh i think its the map, but i'll check that too.