1990 5SFE rough/looping idle

[57nzl]

So yesterday morning I started the celica up, instead of doing the usual cold start and then dropping to a 900RPM or so as normal, I am getting this rough idle of 800-500RPM (has semi-stalled a few times). Now it still "performs" the same so I am not sure? Hopefully someone can help, still fine to drive but embarrassing with the idle sound.

Things that I did this week were -

Oil & filter change.

New head unit.

I decided to take the rocker/tappet cover off to have a squizz but nothing was touched and was replaced in reverse of being taken apart.

Video (sorry bad camera) -

http://imageshack.us/clip/my-videos/231/b73.mp4/

http://imageshack.us/clip/my-videos/29/cl5l.mp4/

Cheers,

Dave

Edited September 11, 2011 by 57nzl

[trentmeyer23]

The vid almost sounds like it's running on 3 cyls. Does it have missing sound at higher RPMs?

Edited September 11, 2011 by trentmeyer23

[57nzl]

Yes, it is noticable throughout the whole rev range. I would of thought it'd be more "sluggish" if it was on 3 cylinders though?

Cheers,

Dave

[trentmeyer23]

What you can do to find out is when the car is running, individually pull and replace each injector plug. If there is a change in idle the cylinder is fine, if there is no change, that is your problem cylinder. Make sure you pull the injector plugs(behind the tappet cover) not the spark plugs.

[57nzl]

Done,

They all seem to idle simular (probably in my untrained ears lol) but the far right hand passenger side when the injector is out is the closest idle to what is happening (sorry if that doesn't make sense)

Cheers,

Dave

[trentmeyer23]

No. 4 Cyl, check your spark plugs and points on the distributor.

[Guest]

No. 4 Cyl, check your spark plugs and points on the distributor.

also check your plug lead.

[57nzl]

The plug leag was off slightly (not sure if that was the problem), I checked the spark plug and it was wet. Still idles poorly though.

Cheers,

Dave

[57nzl]

The actual spark plug plug can be moved around on cylinder 4 while the others can't. That wouldn't be a problem?

Cheers,

Dave

[57nzl]

Also,

What is the Grey/Beige colour thing on the otherside of the timing belt guard? that is near the cylinder head, it seems to run in the same direction as the injector plugs, I did move that to take the rocker cover off. Could that of caused this?

Cheers,

Dave

[95celica]

make sure the hoses on the rocker cover are ok, It is possible that they could of split when you put them back on. That would cause a vacuum leak which could cause the idle to hunt

[57nzl]

Well,

It appears that there is something wrong with the ECU (Mechanic says), If worst comes to worst should I look at getting a aftermarket ECU installed?

Thanks,

Dave

[Guest]

Well,

It appears that there is something wrong with the ECU (Mechanic says), If worst comes to worst should I look at getting a aftermarket ECU installed?

Thanks,

Dave

no point if you arent doing any SERIOUS engine work, just get another 5SFE ecu from the wreckers for $20 and throw it in, the job should take like 20m max

[traceyann]

hi we have just got a 92 celica 2.2 with the same problem so far we have changed the ecu throtel body including throtle sensor replaced dissy and rotor button I only hsve 2 more things it might be and they are

the oxygen sensor and the fuel injectors I don't think it will be the fuel injectors as its like the computer tries to balance the idel also when as slow speed trying to hold at low rev it hops around so have tp put into a higher gear to balance it a bit

ours is drivable as I have adjusted the idel by adjusting the vacum activation screw and adjusted the timming moving the dissy advance (only temperary) I have booked it in for a computer check but can't get in until the 7 Nov

So if we solve the problem before then or when its fixed I will let you know whats been done if you can do the same that would be great.

I hope this saves you the money I have spent as none of the new items have helped as well as resetting the ECU

to do that disconnect the battery for 1\2 hour then reconnect start and isel car for 5 min then drive for 10 min the ECU should reset and adjust to your driving (this didn't work for us) but thats how to reset it

Good luck you will either hear from us soon or we hear from you first see who sorts it out first

[traceyann]

hi we have fixed or problem it was the cold start and the AC vacume sencor hope you have fixed your problem also