Running problems, at a wits end please help.

[Mav122]

Hi there. My car idles cold at 1000rpm dropping to 300rpm when hotter and then dies. Driving it is impossible, I put my foot down in first gear and it wont rev and pick speed up; it does however rev ok when not in gear (or at least to 3000rpm, i've not gone further than that as I dont want to annoy neighbours).

The car has new spark plugs, dizzy cap, rotor arm, ignition coil and all new filters due to recent head rebuild with metal head gasket. I have checked compression and I have 150psi on all cylinders. there are no codes stored when I bridge Te1 and E1 and if I bridge B+ and FP terminals to keep the pump running the problem remains also. I can stop the car stalling by revving it higher but soon as it idles it dies, if I rev it in gear ~(which it wont really do) the engine has no power. With my timing light on any Ht lead the plugs seem to miss a spark every once in a while. The igntion timing is on 10degrees when Te1 and E1 are bridged with engine hot... or as close as damn it with such low revs. Any ideas?

I have had the car for three months and only ever driven it 3/4 way home as HG failed (thus rebuild). I am at a witts end and just want to drive and enjoy the car but am just so frustrated with it. Any help and ideas greatly recieved as im losing interest in it after having spent so much.

[ashley]

Check and clean your Idle Speed Control Valve- they get dirty and clog up.

Also worth checking your coolant sensor is working properly.

HTH

[Mav122]

Idle valve ok and clean . Do you know what readings I should see from the coolant temp sensor at various engine temps?

[toxo]

MK1 or MK2? This is the MK2 forum but your profile says you have a MK1

[Mav122]

Mk2 Turbo, rev1 but engine is rev 2. I had a mk1 but sold it. Need to update .

[megamonkeyman]

If it was me I'd adjust the idle on the throttle body (screw), see if that makes a difference. Make the idle higher?

[Mav122]

even if I did increase idle by turning that screw there is still the problem of it being gutless in gear to the extent of being undriveable.

[Nick Bryant]

You could try a new igniter, thats pretty much the last thing to do with ignition that you haven't already replaced.

[Driftlimits Performance]

Could be all sorts of things. Especially considering the recent HG work.

With that in mind, I'd be checking the static timing first.


ISCV and TPS may need calibration.

Bring it in. We'll fix it in an hour.

[Mav122]

Cambelt timing is spot on, i've double checked that. ignition timing spot, on. I might have a spray round with some carb cleaner and see if it revs up to see if I can find any air leaks. I thought about checking tps but since it ran spot on before the hg went I deliberately havent touched any sensor calibrations. I have calibrated AFM though since problem using vernier caliper and the number stamped on the afm plus a 1 on the front. think it was 83 so I did it 18.3mm. The ignition coil had a crack down both sides so I had hoped it would have been that. Replaced it today and no difference.

I would love nothing more than to give the car to someone to sort it but I have no way of getting it to you since it is undriveable and I have run out of funds for it to pay anyone to do the work. I can pay people in MR2 parts . I have LOADS of mk1 spares! bodywork, looms, manifolds etc and a few mk2 parts, intercooler, cooler fan, fuel rail etc .

I'll check coolant temp sensor and tps if I can find the ohm/volt readings for them at certain heats/throttle posistion tomorrow.

[Mav122]

Right, tonight I checked the tps sensor with my multimeter and it was spot on. I pulled the dizzy apart to check rpm sensor side of it and all looked ok, pickups were slightly rusty but not that bad. I assume to re-install the dizzy you time the engine up via marks to tdc on no1 and line the slot and arrow up on the dizzy and re-insert.

Does anyone know -
How (if you can) to test the three sensors in the dizzy.
the ohm readings for coolant temp sensor cold and hot.

I was checking my vacuum pipes tonight from some diagrams on the internet and my charcoal canister pipes seem to be wrong. I have a pipe from the throttle body pipe straight to sensor. according to the diagram there should be a tsv and some jet inbetween? In pics on the internet the pipe seems to go under the dizzy somewhere, any input?

[Mav122]

Found this site http://staff.osuosl.org/~bkero/bgb/mech ... system.htm (online BGB manual) for my answer to sensor readings.

pipe info would be good though. Would having a pipe from charcoal canister straight to manifold have any ill effect?

[bobhatton]

Just link the two charcol canister pipes at the TB

[Mav122]

This sentance "I have a pipe from the throttle body pipe straight to sensor" is meant to read - I have a pipe from the throttle body pipe straight to charcoal canister.

tested coolant temp sensor and that's ok as well.

Anyone any ideas still?

I might get fuel pressure gauge and check fueling.

[psummers]

I think this is a rev 3 but these pictures might help you check if all the vacuum hoses are in the right place

http://www.mr2turbo.info/pics/engtop.html

[asdrewq]

ISCV and TPS may need calibration.

How do you go about calibrating the ISCV? I did notice it was possible to rotate it when removed similar to the distributor, & the screws have that 'do not touch!' paint mark on them, but iirc I found no mention of calibration in the BGB.

:EDIT:

OP, have a read of this from page 6 onwards:

http://www.autoshop101.com/forms/h26.pdf

3SGTE uses a rotary solenoid ISCV. From reading that it is self-calibrating. Bottom of page 7 in the table you will find the inputs the ECU uses to control idle speed - That should help with your troubleshooting.

[Mav122]

Thanks for pics psummers. those pictures are different from mine as well . I have no big black box on my pcv hoses and my throttle body has one port for vac hoses and the other is blocked - I think the second is for cars with EGR, since mine is jap spec it doesnt have egr . Would only remove it if it did anyway . Thanks for the indepth ICVS info. I read the lot as it was farily interesting. I have calibrated my TPS and have yet to check Ne signal since it says they are the inputs. I'm going to go do some multimeter tests followed by some more headscratching now.

[Peter Gidden]

I have no big black box on my pcv hoses.

Rev1&2 didn't have a catch can. (black box)

my throttle body has one port for vac hoses and the other is blocked.

Rev1 Turbos have one single metal vac pipe on top of throttle body facing O/S.

Rev2+ have two. So you have Rev1 throttle body.

This pic. shows a Rev2 throttle body (ignore the arrows):

I think the second is for cars with EGR, since mine is jap spec it doesnt have egr .

The 2nd vac pipe is just a variation in plumbing from charcoal canister. Nothing to do with EGR valves as Turbos don'e have EGR valves.

[Mav122]

Thanks for that peter. My single vac port on throttle body (port P) goes straight to charcoal canister and nothing else. according to some diagrams I found this is correct less the bimetallic valve which I dont seem to have.

I have done some testing with multimeter and coolant sensor is spot on and idle valve is spot. I also disconnected them with engine running and the rpms changed when dis-connected then re-connected.

I have calibrated the tps and all ohm reading via bgb are spot on, if I however dis-connect tps there is no change in engine behaviour, Even if I rev engine it is the same with/without tps connected. checked codes and there is a code 41 for tps. Should dis-connecting it make rpm difference?

The engine idles fine at 1000rpm when cold but slowly dies the warmer it gets. the warmer it gets the more it seems to start missing sparks on all cylinders. Im beginning to suspect igniter or dizzy as all sensors check out ok but the reliability of both of those components on these cars I thought was meant to be exceptional. If anyone is in Clacton this weekend and minds if I do a swap with them of those two parts to just see if they are at fault I would hugely appreciate it. Ill happily buy a pint down pub for said person .

[stuMR2lee]

I'm in Great Bentley but mines a Rev3 Turbo (conversion) so probably not much help.