93 5SFE 2.2L manual MAP sensor or ECU drama

[gypseyred]

HI Guys may I draw on your wealth of knowledge? Own a 93 2.2L manual camry, done over 300 000km with very limited drama (amazing car). Replaced the distributor last year. Has been starting to lack power from time to time, mostly in the mornings when first started. Now has developed to the engine light on the dash comming on before it stalls. Reads a code 31 when diagnised (MAP sensor circuit). This happens randomly. Starting to become more common have replaced the MAP sensor. To no avail, today 10 min into drive light came on, lacked power, didnt stall, light continued on for some time (car not happy)but didnt stall. Continued to drive until reached home, disconnected MAP sensor car idled better (previously car had stalled when MAP sensor disconnected) drove for a bit until light went off and car stalled. MAP sensor needed reconnecting to start car again. ????? guessing its a ECU problem? Are the ECU's the same in manuals and automatics? Anyone know what the part number is so I can track one down before destroying my car to pull the old one out (its behind the glove box). OR any other sugestions>?? many thanks

[trentmeyer23]

ECUs are different between the two from memory, not sure on the part number. That sounds like there could possibly be a vacuum leak or something along those lines, is there any hissing sounds?

[Guest]

It could be a few things

1) vacuum leak (check all hoses/pips going to the intake manifold for leaks, cracks, etc)

2) f*cked map sensor (try a different map/test your current one with a multimeter)

3) ecu issues (manual/auto ecus are different, although you can use an auto ecu on a manual with a few tweaks)

4) wiring (check all MAP sensor wiring with a multimeter)

[gypseyred]

Have looked for leaks, nothing obvious

have tested and tried other sensors, thinking it is not the sensor, have tested with multi meter- all in range.

About to get hold of another ECU part number 89661-33290 (conveniently located within view once plastic under dash removed) However cant find that number on net anywhere, have got one through local wreckers, it must be australia specific?

It is hard to test wiring when its running without unplugging things. It could be a short in the wiring but how do you find it???.

Generally when you turn it off and on again the fault clears, although it seems to be getting worse and persisting longer.

thanks for the replies, ony other sugestions

[gypseyred]

ECUs are different between the two from memory, not sure on the part number. That sounds like there could possibly be a vacuum leak or something along those lines, is there any hissing sounds?

Perhaps hissing sould. will check or listen with more intent next time it faulters, but its a very intermittant fault. occurs randomly, cant simulate the condition, sometimes when idling downhill sometimes when uphill. wont happen for 2-3 days and it runs like a gem then it has a bad day???