Idle Speed Control problems

4GTuner

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second reading is just telling you closed position setting if you rotate it just alil it'll go up to .9k the reason it recomends .9k ohms is the throtle closed switch doesn't turn off until 1k ohm.

a low reading here could result in a short hesitation after throttle press as the ecu doesn't read any throttle input until the throttle closed switch disengages. you want to set and adjust so the reading number 2 is as close to .9k ohms as possible while staying under 1k ohms after various types of throttle release.

an indicator of a dead tps is no read from the first test.
or the loss of a reading at any point of the travel between closed and open.

the tps is essentially just a potentiometer. it gets feed +5v.

at less then 1kohm the trottle closed switch is active tell ecu throttle is closed.
over 1kohm a % of the 5v reference signal is fed back to the ecu to show throttle position the ecu expects between 0v and +5v on the signal wire you want reading 1 and the reading of throtle wide open to match
 
Ok, so my TPS is fine then? No need to get a new one?
If so, then what could be causing my idling issues? Only thing I can think of is the ECU...
 
your tps is out of adjustment so first i'd bring it back to proper. have you tested the ISC? are all the coils on that good.

no vac or boost leaks

when was the last time the injectors where serviced?
 
No vac or boost leaks, ISC was replaced a few months back (the problem I'm having was occuring before the new ISC was put int, that's why I replaced it - thinking that was the issue).
I have no idea about the injectors. I'll put the TPS back on and make the adjustment - hopefully that's all the issue.
 
Its classic idle surge. Read the first 2 pages of this thread.
pull your isc out and plug it in. Key on and off and compare the isc movements to the video on page2 of this thread.
id say if your isc is still ok, that you have damaged driver ic on the ecu board. Recheck the isc resistance, check for isc movement at key on and look at the driver ic.

your local tv repairman can change the driver ic, you can get replacements from any gold box mitsi ecu.
or pm me for a price and i can replace them for you. I have some new ic, and put them in a holder so you can unplug them to change them next time. I can replace the caps also and recommend doing that if its never been done. Look at the big caps in middle of board and look for bulged caps or brown slime leaking from them.
i can also socket your ecu, move the jumper, so if you ever want to run a burnt chip or ecmlink, you are ready to go.
i can also repair blown tracks on your ecu if required. (Sometimes a blown ic can blow a track also)
 
Sorry to butt in on thread but I have similar issues.

I have replaced the tps and set it up correctly and re checked it.
Also replaced my icv and checked it using the guidelines liked here and it reads the correct ohms across, also checked this a number of times.

What I have is high idle 1800-1500 for the first 10 mins of driving then once at running temp will drop to 900-1000rpm.

I have the bias idle screw all the way in,tried re setting the ecu by disconnecting the battery overnight.

Pulled off the throttle body cleaned it and also the water galleries.checked ever vacuum and intercooler pipes.

The icv was from a v6 magna would the 4cyl icv be any different?
I'm running E3 ecu + injectors + 069 afm + magna TB.

Would changing to the 4cyl icv and perhaps 055 afm help?

Help as I'm lost to what it could be!
 
I had all these problems about a 6 months ago, i replaced and checked almost everything. In the end, i went to the wreckers and pulled 3 magna TB's. After trying 2 that (i assume) had problems the third one had no leaks and the idle surge was gone instantly. Was such a relief after trying multiple things and replacements. After closely inspecting the original TB i noticed gaps in the seals and they all had slight leaks.

Replace your entire throttle body and TPS and see if it clears up
(im running a forged 4g93t, td05 16g, 510cc inj, 609 afm,GSR ECU chipped, socketed and repaired, and magna TB)

EDIT: mine was surging up to 3.5k rpm rapidly until the engine warmed up....
 
 
Nmko what do you mean gaps in the seals?

I had a look at the old icv which tested as faulty.
And also the working replacement that tested fine.

Side by side they are about 2-3mm difference in length so I have swapped the plunger half and seems to have dropped the idle but I'm yet to drive it.

So perhaps one is from a 4cyl magna and the other is a 6cyl with a shorter plunger for a higher idle.
 
It baffles me the number of people who when we ask about boost or vac leaks dont check the throotle plate shaft seals.

@evolved gsr high idle on cold start is normal. Its part of the auto choke so that the car runs smoothly and doesnt stall accessories like ac and high electric load will only worsen the high idle
 
Ok after a long process of elimination I have fixed my idle issues! :)
I bought a 2nd hand throttle body which came with the FIAV. I cleaned it thoroughly like it was brand new. Took off my old throttle body from my car, and put the ISC and TPS onto the 2nd TB I bought. I did this because I know my ISC and TPS are working perfectly. Put the 2nd hand TB back on the car, started it up (cold start it hadn't been started since yesterday afternoon).

Now I don't know if my existing TB and FIAV just needed a good clean and would have fixed the problem but I suspect it was the FIAV on the old TB is not working properly.

Anyways, that ends this chapter of DIY fixing for me. :)

BTW, before I got my 2nd hand TB from gumtree, I went to the local wreckers and to get a TR Magna one - but it didn't look like it would be a direct bolt on. Maybe the wrecker dude got the wrong one or something but it didn't look like it would fit, same with a NA CC Lancer one too.
 
Sweet as^ good work there. The clues were there that your issue was at cold start only. I have a stuffed fiav in the shed, so they do have issues at times.
Some of the magna parts may fit across, but its probably different. I know the v6 tr wont bolt on as the tps sticks right into the bov pipe on the 93 intake. But parts may swap around.
 
Yeah I just went the long way around to fix this problem. Eliminating one thing at a time until there was only one thing left that it could've been.
In the words of Borat - "Great Success!"
 
I did look at buying just the FIAV from Amayama, but both my original TB and 2nd hand screws were stripped so I can't even take them off.
 
Found it - MD614368 for CE9A. According to camskill the following are also all the same MD614568, MD628054, MD628051, MD614978.
Pretty expensive for OE through amayama :-( Will have to look out for some spares in the models mentioned in the thread.
 
Bringing up an oldie here but as the VID links dont work anymore I thought I’d add this in..

Not sure if these are the missing videos from the first page or what but they are pretty decent ones to show you how to test
both the IC’s and the IAC coils.

IC TEST, Not sure if this is a 100% sure thing but I’m sure that some of the gurus out there can confirm or not if this is a good
usable way to do a quick test without having to pull the ECU out etc….

Mine metered out as PIN1-0.579, PIN3-0.579, PIN4-0.577 and PIN6-0.577 so I assume it’s good.

https://youtu.be/qQN2_KWPRzk

IAC Coils

https://youtu.be/oGa1L5lC1SI
 

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