Is200 Misfire

[Ryan2311]

Hi all I posted about a month ago that my is200 had a miss fire since then I have had new coil packs new iridium plugs still got a misfire. It's fine for the first twenty minutes then when it gets warm it starts miss firing again could it be the engine ecu or some thing else does anybody have any ideas. It's a 2001 plate done about 74000 miles manual.When it's plugged in to the machine it only comes up with lean bank misfire no actual fault codes. I'm now at a loose end with the car totally gutted as it has always run beautifully please please help.

[Ryan2311]

Forgot to say the engine management light flashes on as well

[ColinBarber]

what machine is it being plugged into? There should be a fault code, not just a description.

If it is a misfire then it would be good to know which cylinder is causing the issue.

One thing you could try is a fuel injector cleaner.

[Ryan2311]

Not sure what machine it gets plugged into I know when the rac plugged it in its says the same thing.i have had the injectors checked it starts up with a misfire on cylinder 1 the its goes 123 the car still drives when the misfire happens.

[ColinBarber]

more often than not it is an injector issue on the IS200 if the coil pack has been eliminated.

Do you actually feel the misfire? At what engine rpm / throttle position?

[Ryan2311]

Yes I drive for 20 minutes or so and it's fine then you can feel the misfire kick in when I'm at the lights or just on tick over the revs drop to about 750 and its very lumpy it still drives but a loss of power is noticeable.

[ChrisIS200SportTTE]

When I first got my car it was throwing up misfire codes even though the coils were perfectly fine and 6 new spark plugs.

Nobody could find fault so in the end I had to take it to Lexus as I was at my wits end. They diagnosed it in no time. Faulty fuel injector.

I'm not saying this is what's wrong with yours but it's surely something to consider if your coils and plugs are fine. I think they also have much more sofisticated diagnostic computers than say a backstreet garage or the RAC man.

The main difference between your prob and mine is that I knew what cylinder the misfire was on as the code reader would bring up misfire cylinder 3.

[sjrainsford]

There's a number of sensors that could be reporting incorrectly, but not enough to flag up the error, only cause another error to show due to poor running.

Can you tell the car is misfiring, or does it drive fine and just report that it has a misfire?

[ColinBarber]

did you get all 6 coil packs and plugs replaced?

Normally it is just one but just that one can fool the ECU into thinking it is related to another cylinder.

You really need to get somebody to check out all the sensors, monitoring them whilst the fault occurs.

[Ryan2311]

I think that will be my next move take it to a lexus dealer like you I'm at my wits end I just want it back now I'm having the ecu tested by a specialist but is it worth doing that if I'm going to take it to a lexus dealer

[ChrisIS200SportTTE]

He says he can feel the misfire in the post before mine.

Just realised you say it's running lean. So def would look at injectors not putting in enough fuel? Or even fuel pump, blockage in fuel lines somewhere. Really could be anything fella, best get it to somebody who knows what their doing.

[ChrisIS200SportTTE]

Don't be scared of a dealer mate. I paid them £50 to diagnose the fault accurately then went off and got the job done a hell of a lot cheaper than they quoted :)

[Ryan2311]

That's a good price there is a lexus dealer a couple of miles away. Yes you can feel the misfire when your driving and when it's just ticking over but it does not stall

[ColinBarber]

I think that will be my next move take it to a lexus dealer like you I'm at my wits end I just want it back now I'm having the ecu tested by a specialist but is it worth doing that if I'm going to take it to a lexus dealer

there have been a number of faults reported like yours by owners, I don't believe any turned out to be the ECU. There is always a first time but that would be the last thing to try.

Coil pack, fuel injector, fuel pressure, throttle body, throttle TPS, throttle motor, crank/cam sensors, MAP sensor, exhaust leak, air leak in intake, O2 sensors etc.

[ChrisIS200SportTTE]

Agree^^

Massively doubt you have an ECU problem

[Ryan2311]

That's a long list to go through I will ring the local lexus dealer in the morning to se how much it will cost to put on their machine will keep you all posted any more ideas keep them coming many thanks to all who have posted thank you muchly ... Ryan

[ColinBarber]

it is a long list and if somebody cannot diagnose correctly they just go around swapping parts until either the fault is found or you have a new car.

I does pay sometimes to go to a main dealer; they have been trained on the specific vehicles, they have all the diagnostic equipment and most importantly they only work on a few different vehicle models and have probably seen this issue a number of times before - all this adds up to finding and solving the issue quickly.

[Mossyn]

I had similar issue with No2 cylinder misfire.

Fine till the engine warmed up then misfires.

Fitted

New plugs (they were knackered too).....same thing happens

used coil pack.....same thing happens

used injector...PERFECT

Car has been running now for 2-3 weeks and its purrs like a Rolls Royce.

[Ryan2311]

A quick update on my car firstly thank you to all who are giving me lots of info tips and help secondly have booked car in for Friday morning with my local lexus dealer fingers crossed they can pin point the fault will keep you all posted

[Ryan2311]

Well got the car back from the lexus dealer with a number of codes they still can't pin point the fault so here was what the diagnostic report said

P0171 system to lean (AF lean malfunction bank 1 )

P0300 random/multiple cylinder misfire detected

P0301 cylinder 1 misfire detected

P0302 cylinder 2 misfire detected

P0303 cylinder 3 misfire detected

Can anybody shed a light on this now they are saying it needs further investigation

[steve2006]

You need one of these to see into the ignition system and check the firing pulses for the coils and the injector pulses.

Had you been local I would have hooked it up for you but a good diagnostic company should have one.

[stoo_pee]

Sounds like an injector/injector deal to me. Get problems like this all the time in at work on the 3.2 v6 Audi/VW engines

[ColinBarber]

I agree, it does sound like an injector but cannot pinpoint which one. Ideally they should be taken out and tested on the bench to discover which one.

The resistance could be checked first without having to remove them if it is a problem with the coil rather than a blockage.

[Easy_now]

i think i have just started to get the same problem. as i was driving along yesterday the car started to missfire a feel like it isnt running smooth as it should then my engine manegment light and trc light started flashing. did u get to the bottom of the problem?

[ChrisIS200SportTTE]

You just need a diagnostic^

That'll tell you where and why your car is mis firing.