SYMPTOM:
Car starts fine and idles fine and will even rev high if reved very SLOWLY. Even whilst driving on the motorway I can do 80 - 90 or whatever, it just takes time.
But if I open the throttle quickly it stutters and revs drop straight away and will not increase if the trottle is held open.
PROBABLE CAUSE:
I did a compression test because the engine was overheating all of a sudden. Could'nt find any leaks and it kept filling the overflow tank. Friend told me it could be a bad Head Gasket.
However I did the test wrong.
I took one spark plug out at a time,
Screwed in the pressure gauge,
Unplugged the plug lead from the dispributer (from the plug i'd taken out),
then RUN the engine for a few seconds - reving a few times, noticing the different readings.
Also made the mistake of leaving off the Resonance Duct when testing chamber 3.
TESTED:
(Following Troubleshooting from Manual F2-048)
All plugs were in ok condition when doing compression test:
![Image](http://a293.ac-images.myspacecdn.com/images01/5/m_a6a00cc7fd2590e0ffdeb5c5aa26129c.jpg)
I did test the sparks on the inlet manifold during the compression test but just got dull yellow sparks.
I've tested the PD between the battery GND and engine (0.3v)
Plug leads are about 20% higher resistance than spec. I think chamber 1 was 21k ohm.
Took off distributer cap. Terminals were covered with white oxide (I think). So dremeled them clean and shiny.
Primary and secondary coils are in spec. Primary was 1.2 ohm but then measured resistance of probes which were 0.5 ohm. --> 0.7 ohm
VAF resitance open and closed is in spec.
(However - NOT LINEAR - is this OK or NOT OK??? Read a post about this but still not sure)
Checked for vacuum leaks. None - I think but not had manifold off.
Taken off throttle body which is covered in oil and inside manifold.
Adjusted throttle position sensor from 0.63mm on/off to 0.5mm as spec.
VRIS solenoid next to air filter is working and vacuum is present. When open throttle quickly vac goes but when I open throttle slowly vac stays.
Have not got any error codes from ECM but don't know yet if there are none to show or if I just can't get them.
Can't test manifold pressure but when throttle is opened quickly there is very high vacuum then nothing.
Not checked ECM yet (2F, 2I). Thought it was much harder to get at than it is.
Can't check fuel line pressure but fuel pump under back seat is working. Took out while engine was running. (bit dodgy
![Wink :wink:](./images/smilies/icon_wink.gif)
Can't test timing advance properly but will slightly adjust distributer.
Can't think of anything else other than previous owner (friend) had symptom before but took it for a spin and it went away.
Please help. I'm desperate for my car back.