Couple of Q's on 4afe/5afe engine

[AE91Sprinter]

http://i2.photobucket.com/albums/y50/et ... G_1959.jpg

When i jumper te1 and e1, this little fella clicks repeatedly - this normal?

secondly, on the throttle body, theres the inset idle adjustment screw, and theres another screw (allen head rod with bolt attached) that appears to be a stop for the butterfly valve... whats the deal with that screw, and what does it do?

http://i2.photobucket.com/albums/y50/et ... G_1960.jpg
far right in this pic

Cheers

[CozmoNz]

second one is so you can adjust it to completely "shut" since if you remove that bolt, the throttle will pull it to a point where its past shut and its open again hahaah.

aka the throttle stop.

[AE91Sprinter]

right, so i adjust that bolt until its basically shut to do the timing, yes? so the TPS is not effected etc?

[sergei]

NO! TPS will be greatly affected. The car will run jerky on light throttle.
I guess your idle control is ECU controled, when you bridge across TE1 with E1, the ECU shuts off ISCV. if it is late 5A you cannot adjust idle on those (no adjustment screw).

[AE91Sprinter]

Its an early 5afe, 1987. The person before me had been using this throttle stop screw as an idle screw adjustment, as a result the cars timing was off by miles and the ECU seemed somewhat confused. Had a huge flat spot from 2-3krmp. Have adjusted the idle speed via the correct screw, and jumpered the ecu via TE1 and E1, and redone the timing. Have checked the TPS and re-calibrated it the 4AFE way (the TPS is identical as far as i can tell, and the procedure went well).

The car runs ok now, much less severe flat spot, accelerates evenly, idles pretty well. However, id like to know what i should do with the throttle stop screw and its exact purpose, as im fairly confused as to what the stop does; is it meant to be completely closed on idle? Basically i just want to know exactly what it does so i can tune this thing well.

On a side note, im having starting issues, hence the question about the first photo and the clicking, im assuming thats a cold start injector or a fuel solinoid or something, and the clicking could suggest its dead...

The person who did work on this car before me had less of a clue than i did, its basically wading through someone elses problems and correcting them, not fun.

pretty much found the info i need here - aarc.epnet.com

[sergei]

the stop screw stops throttle butterfly sticking (jamming) after closing. I don't think your car has cold start injector. that solenoid is either AC idle up or electrical load idle up.

[AE91Sprinter]

Ok, thanks Sergi. I'll take it to bits today, reset it to closed + reset the TPS sensor, redo the idle speed + timing. I think my bypass is clogged or theres an airlock somewhere in the coolant too, so i guess i'll drain and flush with new coolant (i havent done it yet, so i may as well).

[AE91Sprinter]

right, did all of the above barr flushing the system. Still has starting issues, dont have a garage so didnt get the coolant flush or re-check the error codes; too wet for anything today, unfortunately.

Id love to know what the hell that blue connector on the intake manifold is connecting to....

more googling and searching i think.

[Lloyd]

Did you manage to get any fault codes out of it jumping the terminals? And is the air con on while the terminals are jumped? Pretty sure you're supposed to have it turned off, one of the conditions of getting the codes out that way. So could possibly be air con idle up or something

[AE91Sprinter]

aircon was definitely off.

Seems odd, isnt throwing codes, but the gap is 4.5 seconds instead of the smaller gap that would normally indicate 1 (or so im lead to believe). Its definitely 4.5 flash 4.5 flash 4.5 flash, so im guessing its meant to be code 1...

Im starting to wonder if its fuel pressure, ill try jumpering the pump this morning. The cold start in the mornings is the only problem i have with it now... seems to go well other than that.

On googling, the valve is either IVSC or the VCV valve, i forget (twas a couple of days ago). I found the information in the technical articles i posted into the FAQ. When its jumpered its meant to go 'full duty' so the clicking is quite probably normal. Im going to flush the coolant today + check the thermostat, and whilst im at it ill check the coolant idle-up bypass in the throttle body.