help 4age wont rev!?!?

[Bean]

have you checked if the timing advances to 16° if you take it out of diagnostic mode... some cars (mine for example) have troubles with getting into diagnostic mode due to bad wires at the connector... resulting in 6° lack of ignition timing
on another note have you inspected your distributor for hairline cracks or exessive wear? this could lead to bad timing as well...

[ep71]

timing may not be bang on 16 degrees btdc but that would only cause it to be slightly down on power not for it to refuse to rev altogether. ive tried 2 different distributors, 2 different throttle position sensors, 2 different fuel pumps but still no improvement

[jondee86]

The ECU needs a signal to tell it to increase fuel when the throttle is
opened. This comes from the flapper opening (AFM) or from the MAP
sensor. At idle the engine has very little fuel, and if the ECU does not
increase fuel when you open the throttle, the engine goes... blaaagh

Check that your load sensor (AFM or MAP) outputs a signal that varies
with load. Push the flapper open by hand on an AFM engine and monitor
the pins (can't tell you which ones offhand). On a MAP sensor apply some
vacuum by sucking on the hose (you can get your best g/f to help) and
see if you get a varying output.

Best if you can monitor the voltage at the ECU end of the wiring harness,
because that way you are checking the wiring as well. I'm pretty sure all
the correct test values are in the FSM.

Cheers... jondee86

[ep71]

surely if the map sensor was gone it would be showing a flash code?

[jondee86]

I don't know how the ECU monitors the MAP sensor to bring up a fault.
Again, from memory, there are three wires; an ECU ground reference, a
5V ECU input, and a variable signal output. If the ECU doesn't monitor
the variable signal, then it might not throw a fault if the signal is missing ?

If your spark and timing is good, then it can only be air or fuel that is in
short supply. Either the injectors are not being told to squirt more fuel, or
they are trying to squirt, but the fuel is not there (= fuel flow/pressure
problem).

Cheers... jondee86