I finally got a working multimeter and ran diagnostics on my TR Magna receiving the code 41. A problem with the injector.

I used a digital multimeter to test the injector coil resistance in all of the injector connectors and they all gave a reading of 16.0 (the requirement is 16 plus or minus 3, so that's good). But now I don't know what to do.

What do I check next? What could the problem be?

The car's been idling low, check engine light comes on while accelerating, the check engine light is saying there's something wrong with the injector, although it's not the coil resistance. The car's also dual-fuel.

If it has the same problem on either fuel, and your gas system is just on one of those rings/gas carby things and not somehow through your petrol injectors, then I don't think they are the problem. Can you clear the codes and see if any return? If the injector code returns try cleaning the plugs for them in case its a dodgy connection causing an error.

Yep, reset the coding by disconnecting battery for few min. Unfortunately that will reset your autobox too if your's have one... Then again, you did mention it appears while driving.
Cannot remember or don't have the book handy now, but is that code same for Immobiliser errors? That often bothers our cars.

I hope this isn't a long shot, or a waste of your time, but often something with a coil in it - be it injectors or ignition coil, test fine with a multimeter but break down under heat and high duty cycles. You could try another set of injectors from the wreckers, or get them tested on a test rig that loads them up.
Alternatively, it could be at the ECU end, with leaking capacitor(s) causing signal loss at higher rpm and causing the CEL. The ECU is located behind the glove box, on the left. Easy enough to take out and open up.
Check injector connections for corrosion too, you never know.

At the 45000 km service for my Pajero, the service manager told me that they had checked the ECU for faults and had recorded a fault with No 1 injector. They didn't replace it - simply pushed the plug back on> It had been running fine and there was no difference afterwards, I reckon it was just a load of crock, but maybe you have a connector problem?

Okay well I cleared the codes and it came back, 41 for the injector. The check engine light doesn't come on every time I accelerate, only every now and then. The plugs are all connected perfectly and clean. It was suggested that I flush the injector, so I might get that done professionally at a mechanic. What else could it be?

Damn, $280-$320 to get the injectors cleaned at the mechanic. Definitely wasn't budgeting for that. I think I'm going to try to work out the exact problem before doing anything like that. No point in spending $300 on cleaning the injectors if that's not the actual problem.

Does anyone have more ideas as what could be causing it? Or a guide on how to check the wiring/test the injectors?

Try u-pull-it for some injectors off a clean looking 4cyl. They have about 9999 2nd gen magnas last 5 times I looked. Surely they fit inside something. Usually I buy a few bigger things and take home a centre console tray half full of screws and plugs and a few globes etc, they have a quick look and might charge you for an interior light or a dash clock if its in there but usually say just take it, its only off a magna.

Cleaning the injectors will not cure an electrical fault that affects the operation of the injectors. If it's occuring on gas as well as petrol, it cannot be injector related. I'm not sure exactly what is the problem with your engine but I'd check all the easy items first - plugs, leads, distrib cap, igniter/coil. Also try gapping your plugs to a smaller gap - this can sometimes cure missing/hesitation especially in dual fuel cars.

Cleaning the injectors will not cure an electrical fault that affects the operation of the injectors. If it's occuring on gas as well as petrol, it cannot be injector related. I'm not sure exactly what is the problem with your engine but I'd check all the easy items first - plugs, leads, distrib cap, igniter/coil. Also try gapping your plugs to a smaller gap - this can sometimes cure missing/hesitation especially in dual fuel cars.

Well that's weird, it happens with petrol and LPG. But the code is definitely for the injector. It also idles really low and has a bit of trouble starting sometimes especially when cold, after driving for about half an hour the idle goes back to normal. Thanks for the advice.

Well that's weird, it happens with petrol and LPG. But the code is definitely for the injector. It also idles really low and has a bit of trouble starting sometimes especially when cold, after driving for about half an hour the idle goes back to normal. Thanks for the advice.


The fault code that you have got from probing the diagnostic connector came back with code 41 as referenced to the service manual.
This does not nessesarily mean that its an electrical fault causing this sensor that is being triggered which is setting off the fault code into ECU and causing the check engine light to come on.

Here are a few things you can try. Straight out of the Haynes manual

1. Check all electrical connections (any related to injectors, also check grounding point connections are ok) clean if dirty or build up of corrosion whereever needed)

2. Remove air intake duct from throttle obdy and check for dirt, carbon or other residue built up in the throttle and on or around the throttle plate - Not sure how this affects injectors directly but its easy enough to check and clean with carby cleaner and a dry rag.

3. With the engine running check each injector one at a time for operation. (The manual says you can check with a stethoscope but i dont imagine youd have one lying around unless you were a doctor or have friends who are doctors)

You can also check by putting the tip of a screw driver against the injector and pressing your ear against the handle to listen for click noise. If its clicking then its operating.

4. With the engine off and fuel injector electrical connectors disconnected. Check resistance of the injectors one by one.
I could not find the values it should be in my Hayne manual however it is likely to be in the mitsi service manual thats you have.

I hope this helps mate. Try these before doing anything expensive just yet as it could save you a mint.

Let us now how you go.

Thanks

Have you checked the charcoal canister purge valve operation yet? (I'm presuming 2nd gens have one)...this can throw up unusual codes and give strange problems in other cars.

The fault code that you have got from probing the diagnostic connector came back with code 41 as referenced to the service manual.
This does not nessesarily mean that its an electrical fault causing this sensor that is being triggered which is setting off the fault code into ECU and causing the check engine light to come on.

Here are a few things you can try. Straight out of the Haynes manual

1. Check all electrical connections (any related to injectors, also check grounding point connections are ok) clean if dirty or build up of corrosion whereever needed)

2. Remove air intake duct from throttle obdy and check for dirt, carbon or other residue built up in the throttle and on or around the throttle plate - Not sure how this affects injectors directly but its easy enough to check and clean with carby cleaner and a dry rag.

3. With the engine running check each injector one at a time for operation. (The manual says you can check with a stethoscope but i dont imagine youd have one lying around unless you were a doctor or have friends who are doctors)

You can also check by putting the tip of a screw driver against the injector and pressing your ear against the handle to listen for click noise. If its clicking then its operating.

4. With the engine off and fuel injector electrical connectors disconnected. Check resistance of the injectors one by one.
I could not find the values it should be in my Hayne manual however it is likely to be in the mitsi service manual thats you have.

I hope this helps mate. Try these before doing anything expensive just yet as it could save you a mint.

Let us now how you go.

Thanks


Have you checked the charcoal canister purge valve operation yet? (I'm presuming 2nd gens have one)...this can throw up unusual codes and give strange problems in other cars.

Thanks guys, I'll definitely try them. A couple of questions, how do I check if the charcoal canister purge valve is working? And is there a way to check if all the electrical connections are working?

Thanks again.

We checked all the injectors with a screwdriver, all work. We checked the coil resistance, all had perfect resistance. We did notice that an air tube connecting the ISC motor and the Plenum Chamber was loose, so we tightened that and it seemed to fix the low idling problem, we are now disconnecting the battery to wipe the codes, then we'll go for a drive to get some injector cleaner and see if the light comes back on.

Also, when we took the air intake duct and air cleaner off, there was a bit of mangled metal. I realized that it was part of a honeycomb grid filter behind the air cleaner, so now there's a piece missing from the filter:

http://img231.imageshack.us/img231/6820/filtere.jpg

Any idea on how to get a replacement?

Well we seemed to fix the problem causing the check engine light. But now it's idling low again and "misses" a lot when idling.

What RPM is it idling at when in Park or Neutral (when stationary) ?
What RPM is it idling at when in Drive or Reverse (when stationary)?

Its more sounding like a failing if the ISC for the low idling.
I have a spare ISC for the 2g 4cyl i can mail to you if you want.
You can pick them up at wreckers for cheap otherwise.

Bit confused by a previous post you mentioned 'air tube to the ISC Motor' ?
I think you mean a tube that is found on the top of the throttle body plenum yes?
The ISC is tucked beneath the throttle body.
You would have seen it when you removed the air intake ducting to the throttle body.

Did you disconnect the plug connector to the ISC and check for corrosion or bad connection?
Also unplug the connector to the TPS to check also for corrosion and bad connection.

Your getting there mate. Closer to finding the offending part or parts causing poor idle. Glad you got the fault code cleared up,

Let us know

What RPM is it idling at when in Park or Neutral (when stationary) ?
What RPM is it idling at when in Drive or Reverse (when stationary)?

900 in Park and around 700 in Drive.


Its more sounding like a failing if the ISC for the low idling.
I have a spare ISC for the 2g 4cyl i can mail to you if you want.
You can pick them up at wreckers for cheap otherwise.

Bit confused by a previous post you mentioned 'air tube to the ISC Motor' ?
I think you mean a tube that is found on the top of the throttle body plenum yes?
The ISC is tucked beneath the throttle body.
You would have seen it when you removed the air intake ducting to the throttle body.

Did you disconnect the plug connector to the ISC and check for corrosion or bad connection?
Also unplug the connector to the TPS to check also for corrosion and bad connection.

Your getting there mate. Closer to finding the offending part or parts causing poor idle. Glad you got the fault code cleared up,

Let us know

I'll check first, I'm hoping it's just not set correctly, would adjusting the throttle stop screw help the idle? Yes I think that's the tube, it's connected to the plenum, about as thick as my arm and only about six inches or so long. Okay, I'll check both plugs.

The main problem with the idle is that it keeps 'missing', probably every three or four seconds.

Thanks guys, I'll definitely try them. A couple of questions, how do I check if the charcoal canister purge valve is working? And is there a way to check if all the electrical connections are working?

Thanks again.

I'd first locate the charcoal canister, then trace the vacuum lines back towards the inlet manifold - one of them will go to the purge valve solenoid which is probably the size of a relay and have some wires attached to it. This solenoid is designed to isolate the charcoal canister from the the inlet manifold when idling or when the engine is cold - above idle or when warm it releases and this allows the manifold vacuum to suck the fumes etc from the charcoal canister. If the purge valve gums up and stay open at idle, it introduces an excess of air to the inlet manifold at idle and you can get misses etc. I'd check it by removing the hose that goes from the purge valve to the canister when the engine is idling - there should be no vacuum, but when engine speed is raised there should be some vacuum. Never done this on a Magna but have done on other cars...it's a rare fault but one that can cause a hard to track down problem.
Good Luck.

900 in Park and around 700 in Drive.



I'll check first, I'm hoping it's just not set correctly, would adjusting the throttle stop screw help the idle? Yes I think that's the tube, it's connected to the plenum, about as thick as my arm and only about six inches or so long. Okay, I'll check both plugs.

The main problem with the idle is that it keeps 'missing', probably every three or four seconds.

Just to answer your question on throttle stop screw. Dont adjust this screw. This is factory set.

Your car is idling low as factory should be approx 1100-1200 RPM in Park or Neutral and 700-800 in drive or reverse gears.

Just so there is no confusion the idle can be adjusted with the idle adjustment screw just above the TPS (Throttle position sensor).
Its facing directly forward on the throttle body assembly.
Clockwise reduces RPM and Anticlockwise increases RPM.
Start your car and have it in Park with handbrake on and use a screw driver to adjust.
You will here the engine increase revs as you turn it anticlockwise. Adjust it to 1100 RPM. Jump in the car and whilst keeping your foot on the brake and with handbrake on select the Reverse or Drive gears to see that the RPM sits between 700-800 RPM.

As i mentioned before i'd be looking to replace the ISC. After many years of trusty service these parts can begin to fail. The above mentioned idle adjustment can work to correct the idle speed for a while however it does not fix exactly whats causing the low idle. Thus why i suggest replacing ISC as its not hugely expensive and you could find one at a wreckers for cheap.

Also if your car is "missing" then certainly look towards what HAKO mentioned. If the purge valve is gummed up then the introduction of excess air be causing your issue.
I actually have been having some similar troubles just recently and might have a look at this myself and clean it out if its gummed up.