Hey guys,

This might be a bit of a read, so sorry about that, but I want to get as much information as I can about the problem.

This 2001 KJ Verada came in for the 195,000KM service. The timing belt was replaced, and the rear bank spark plugs were replaced.

Once it was finished, I took the vehicle for a road test. Driving normal was fine, but as soon as I accelerated over 3.5+RPM, the vehicle cut back on power (or sort of felt like it had a blocked fuel filter) and the TCL light started flashing, and the light kept on flashing, even when I came to a complete stop. The only way to stop it was to turn the engine off and restart, but then the same thing would happen again.

This was a while ago, but today the vehicle came back because the customer wanted the problem fixed, so all day we have been trying different things.

Today we also had a TL Magna come in, so we tried swapping parts off that to try find the problem.

What we tried today:
-Swapping the Air Flow Meter (no difference).
-Removing the Catalytic Converter (thought it may have been blocked, no difference).
-Swapping the Traction Control Solenoids (no difference).
-Unplugging the ABS Module (no difference).
-Replacing the Fuel Filter (no difference).
-Swapping the ABS Fuse (no difference).

BUT... When I put the ABS fuse from the KJ Verada into the TL Magna, and took the TL for a roadtest, the TCL light came on, and so did the engine light. So I swapped them back, the lights didn't come on, swapped them again, the lights both came on. So I fitted the fuse from the TL into the KJ, but it didn't make any difference.

Customer says that the problem only started after the timing belt was replaced (or the 195,000KM service). We removed the timing belt covers and made sure all the timing marks were aligned, which they are.

We are running out of options now, so anyone have any suggestions? Customer took the car back today, but will be bringing it back in July, so next we were going to check fuel pressure, but I don't think that's going to be the problem.

Thanks in advance for any help.

Check the alternator for voltage drops.. Failing that, check for vacuum leaks, or maybe check your EGR connector is tight. These have been symptoms for others in the past.

When you changed rear plugs did you remove the manifold completely or just raise it up enough to change plugs? Maybe vacuum lines aren't connected in the right place. Did you try and clamp the vacuum hose from solenoid to throttle body that sucks the butterfly shut.

I would expect that if the problem was with the vacuum lines, it would be more apparent at idle, not full power. Is the engine smooth at idle?

Thanks for the advice so far guys :)

Yes the engine runs very smooth at idle, and drives fine normally, it's just when you accelerate harder and go over a certain amount of revs, then like I said, the TCL light flashes, and will continue to flash until the engine is switched off, then once you start it up it is fine, until you do the same thing again.

just a guts feeling from a noobie..
could this be corroded sockets in fuse box? or any sort of corrosion or conductivity problem in the electrical system ? preventing enough current from being delivered to the engine when rpm is high?
if thats the case , alternator and battery voltage would still show normal, but engine wouldnt get the same volts.

(ok im hiding now)

Diagnostic codes can be retrieved from the TCL system which might help narrow the problem down. The loss of power can be explained by the TCL system reacting to an apparent traction loss and reducing power; it later decides that there's a problem of some sort and flags it by setting the TCL light ON. The warning behaviour in the TL may simply be a difference in reporting which internal self tests for various subsystems have failed, with the TL reporting more issues. I note that one of the TCL codes relates to ABS system issues, so there may be more to be checked with the sensors used by both the TCL and ABS systems.

That's actually one big thing that I forgot to mention. At work we have 2 different diagnostic scan tools, an "Ultrascan" and a "G Scan", both scan tools were able to check for engine fault codes and live data as normal, but both were not able to access TCL and ABS, kept coming up with "communication error", now this wasn't just with the KJ Verada, but also with the TL Magna, and I am pretty sure if I tried it with my TJ Magna, the same thing would happen also.

Sorry for mentioning this in the first post but I completely forgot.

Well it might be the fact that it's not a OBD1 scanner. Magna's are pretty oldschool and require OBD1 compliant devices. Also, pretty sure most of those are MUTII devices.
You can get evoscan 1.3 cables off the internet for under $100. They work perfectly with the magna's.

Needs to be scanned mate, only a few units scan these systems. You would be surprised how many workshops send cars to us for diagnosis, is generally cheaper than spending a day of labour. Also some of the parts you swapped between cars are not compatible, most you tried are not even tcl related. As a customer I would be furious if I found out my car was used as a test pig :)

Needs to be scanned mate, only a few units scan these systems. You would be surprised how many workshops send cars to us for diagnosis, is generally cheaper than spending a day of labour. Also some of the parts you swapped between cars are not compatible, most you tried are not even tcl related. As a customer I would be furious if I found out my car was used as a test pig :)

Yeah I suggested taking it to you, but my boss said he doesn't want to take it that far lol, and the guy that drives the TL Magna wasn't worried because its not even his, it's a fleet vehicle haha

Also I spoke to Brendan about it over the phone (because you weren't there), and he said that the TL will be the same and I would be able to swap the parts and see if it fixes the problem. The air flow meter had the same part numbers on them, that why we tried that, and I don't know why they tried removing the catalytic converter and changing the fuel filter, I think mainly because they were running out of ideas haha

That's actually one big thing that I forgot to mention. At work we have 2 different diagnostic scan tools, an "Ultrascan" and a "G Scan", both scan tools were able to check for engine fault codes and live data as normal, but both were not able to access TCL and ABS, kept coming up with "communication error", now this wasn't just with the KJ Verada, but also with the TL Magna, and I am pretty sure if I tried it with my TJ Magna, the same thing would happen also.

Sorry for mentioning this in the first post but I completely forgot.
According to the WS manual the TCL and ABS codes are supposed to be retrievable via the flashing lights method the same way as ECU and trans codes, ie earth pin 1 of the diagnostic connector, switch the ignition to ON, watch the respective lights for a sequence of long (1.5s) flashes followed by a sequence of short (0.5s) flashes.

Hey guys, I would like to thank everyone that has given advice on what to try and everything. I thought I was doing the right thing by trying to help fix the problem by asking for advice on here, mainly because my boss who is working on the car really has no idea and is running out of options, but it seems that he isn't listening to a word I say, and also doesn't really believe me, especially when I told him about Magnas having an OBDI connector, he still thinks his scan tools will work (so he keeps trying and of course doesn't get anywhere), and he is convinced that it is a fuel pressure problem, or the timing is out.

Anyway, it's made me think, why do I even bother, i'm using my free time to try and help with a problem that hasn't got anything to do with me, and he doesn't even appreciate it. So I decided to just let him try and work it out for himself, he seems to think he knows what he is doing. If I find out what the problem is/was, I will still post it here to let everyone know, in case someone else has the same problem in the future. I just figure, whats the point in telling him what to try and check if he doesn't listen anyway, and he keeps checking things that wouldn't have anything to do with the problem.

Thanks once again, at least I appreciate everyones help :)

lol Anger and frustration really get in the way of intelligent trouble shooting.

Boss angry.

Stay out of the way of Angry Boss, or he will think you are a smartarse. lol

lol Anger and frustration really get in the way of intelligent trouble shooting.

Boss angry.

Stay out of the way of Angry Boss, or he will think you are a smartarse. lol

Haha that's right, but he is an arrogant guy and is hardly ever in a good mood, just thought I would try and help to make things easier but I think I make him more angry and confused by giving him advice haha.

Has anyone found a solution to this problem mine started early in the year and I was worried about it and it suddenly stopped. Now its starting again showing me the TCL light and shortly afterwards showing the engine light. Wanna get this problem fixed bc its really annoying.
Thanks Guys for any help :)

have noticed "TCL OFF"" light flashing in a 2000 KJ Ei - TCL and Cruise Control.

For me, issue is on a dead-cold start-up (after sitting overnight) - car will start immediately and idle smoothly. But it will not rev beyond idle. TCL OFF light seen to be flashing on two consecutive days this problem has occurred.

Yesterday, re-starting car was immediate fix - after we had idled along a back street a short while and been generally confused. Today, the problem was noted whilst in motel carpark and more refined fiddling was done by us - to no good effect.

Eventually, we waited in car while letting it idle and warm up. As we noticed idle speed dropping back a wee bit as engine warmed up - we gave it a bit of throttle and were back in business. Fiddling with Air-Con on/off made no diff, Fiddling with the "TCL" switch near key made no difference. Pulling on throttle cable under bonnet achieved no change to idling. Re-starting car this morning made no difference a few times - eventually it just corrected itself. Never saw the "Check Engine" lamp light.

A look at the PDF Workshop Manual in EFI and TCL chapters has me wondering about Accelerator Position Sensor (TCL cars only) or Throttle Position Sensor. If problem occurs tomorrow morning, we'll look for Codes using the F;ashing Light sequence, and maybe run a Multimeter over the APS and TPS - esp if we get a Fault Code that seems relevent. We drove 300kms plus today - with heaps of stops and starts in various towns and plenty of highway-speed cruising - no issues for me except on dead-cold start-up. Idling is smooth - on start is the brief initial flare of revs then smooth idle, just no throttle response to pedal. No stalling on giving accelerator or lifting accelerator - just consistent idling.

I pretty much never post but the 'TCL' light came on in my car about a year or so ago. After spending close to $2,000 it was solved.
The TPS failed in the car, caused power to be lost (kept driving, not well however), and I limped it to Mitsubishi Dealer near me. After over a week of them playing around with the car they isolated the cause. There are 2 sections to the TPS and to buy new they cost a freaking fortune, managed to get a 2nd hand assembly to get it going again but that cost $$ still as wreckers know they are expensive parts.

This may or may not help, but it was my problem and I hope other people don't have to spend so much to fix it. My car is a 2002 Reg Dec/01 KJ (Series 1).

This is why you should have brought the car to me :). Quick test would have told anyone who knew what they were doing what the issue is and the parts are in my shop already

Elwyn, as stated mate, clean your TB, the plate is sticking

Issue was open circuit, which frankly I could have found with a multimeter rather quickly myself... Learned my last lesson with dealer servicing.

As you are near my work I may consider getting you to have a look at my idle issues if what this topic says and an O2 sensor doesn't help

Thanks for Reply Mal - I will look into that (it had crossed my mind, briefly, then I went hunting complicated TCL stuff and confused myself). Will keep you posted! Thanks heaps, all!