[tobbsi]

Ok so that didn’t help. I Think that you wil have try and do some diagnosing. Eric has a guide for Crank/No Start issue and that is probably the route to go. In general we could probably say that it is the fuel pump but there are other components involved as well. However for a easy test it would be good if you got it running on something else, like propane. Then you knew you had a fuel delivery issue. Does it have spark?

[tobbsi]

Ok so that didn’t help. I Think that you wil have try and do some diagnosing. Eric has a guide for Crank/No Start issue and that is probably the route to go. In general we could probably say that it is the fuel pump but there are other components involved as well. However for a easy test it would be good if you got it running on something else, like propane. Then you knew you had a fuel delivery issue. Does it have spark?

[tobbsi]

Hi again!

I’m glad to hear you solved it. Some models of the V40 have a problem where the relays to the lowbeam headlights can burn out. They are located in the CEM (Central Electronics Module) behind the dash and can be replaced with a little bit of soldering if you ever run into that problem. Just a tip for the future!

[tobbsi]

Hi again!

I’m glad to hear you solved it. Some models of the V40 have a problem where the relays to the lowbeam headlights can burn out. They are located in the CEM (Central Electronics Module) behind the dash and can be replaced with a little bit of soldering if you ever run into that problem. Just a tip for the future!

[tobbsi]

Ok so do you think you only ran out of gas?
I’ve been checking out your model and I’m afraid I don’t know alot about it so I’m probably not much help. If you didn’t get low on gas and it actually is something wrong with the pump also check if there is a relay controling the pump before you replace it.

[tobbsi]

Ok so do you think you only ran out of gas?
I’ve been checking out your model and I’m afraid I don’t know alot about it so I’m probably not much help. If you didn’t get low on gas and it actually is something wrong with the pump also check if there is a relay controling the pump before you replace it.

[tobbsi]

Hi!

If I may fling myself into this problem. It is very nice to get help from someone who knows the model specifically so try to take his advice. I’m just thinking about a variable.

JS: Does the 100 have a DME relay or what version of Motronic is it? Is it L or LH-jetronic or some newer Bosch system? If it is newer then I’m afraid I am no help 🙂

[tobbsi]

Hi!

If I may fling myself into this problem. It is very nice to get help from someone who knows the model specifically so try to take his advice. I’m just thinking about a variable.

JS: Does the 100 have a DME relay or what version of Motronic is it? Is it L or LH-jetronic or some newer Bosch system? If it is newer then I’m afraid I am no help 🙂

[tobbsi]

Hi!

You are probably right in your own guess. It is likely the thermostat that somehow got stuck open. Does the engine take longer to warm up than it did before. In that case it is a good hint that the thermostat is the problem.

[tobbsi]

Hi!

You are probably right in your own guess. It is likely the thermostat that somehow got stuck open. Does the engine take longer to warm up than it did before. In that case it is a good hint that the thermostat is the problem.

[tobbsi]

Hi Eric! If you could get a hold of a diesel powered car that would be awesome! here in Europe diesels are climbing in sale big time and today there are actually really good. For personal reasons it would be great if you bought a 80’s Porsche. However I know it perhaps wouldn’t be practical for you 😀 Keep up the great videos! Best regards from Sweden.

[tobbsi]

Hi Eric! If you could get a hold of a diesel powered car that would be awesome! here in Europe diesels are climbing in sale big time and today there are actually really good. For personal reasons it would be great if you bought a 80’s Porsche. However I know it perhaps wouldn’t be practical for you 😀 Keep up the great videos! Best regards from Sweden.

[tobbsi]

Hi again everyone,

I have now had some time over to spend on my car. And money! I took a break from the engine issue and spent some time fixing my stuck door locks. They were corroded in place so to speak. Back to the engine. I have now replace to cap, rotor and the spark plug wires. It did much difference. It now sounds much smoother but there were still some misses now and then. Now I didn’t really know what to do so I called a guy that has worked on a lot of 944s and at the moment has my neighbors car to do some suspension work. I had to take the whole story about the engine and some history what had been done to it before. After some thinking and talking about fuel system and God knows what we ended up in a mixture problem again. Here is the thing.. What my small brain didn’t understand before is that the mixture screw on the AFM only corrects CO on IDLE. Not when the throttle is off the TPS idle position! In other words you can lean the mixture out so much that it starts to misfire at times. I thought the mixture was good before because when I buried the pedal in floor it ran good. Obviously Bosch designed this system this way for some reason I don’t know but perhaps the engine needs a bit more fuel at idle to run smoothly? Anyway I turned the screw in a couple of turns and the misfire went away completely and also the engine rpm rose a lot. I corrected the base idle on the throttle body and removed the jumper cable and now it works like charm. The question is how it could have become this way.. I have a receipt from a Porsche dealer where they adjusted the CO after the faulty AFM was replaced so it should have been good! The things is this I believe: Because of the faulty Idle Speed Valve someone had tinkered with the throttle body and therefore the base idle was way to high. Even after I put things right it used to idle at about 1100 rpm. Because the idle was high the dealer had not got the mixture right for the idle. So now that I fixed the ISV and the idle now is back to normal 800 rpm and the base idle set to 840 rpm the mixture is too lean at that engine speed. I am not an expert on this but I believe it must have been something like this. Later on when I’m going to take the car out of the garage and start driving it I will have to take it to a shop with a gas analyzer and correctly set the CO.
For those of you who wonder how to do that:
1. Warm engine up
2. Defeat idle stabilizer (ISV) at diagnostics port
3. Connect a rpm meter to the ignition coil
4. Adjust CO with a gas analyzer in the tailpipe and make sure the base idle is at the right interval of 840 +/-40 rpm ALL the time.
5. When CO is correct and idle is correct disconnect the rpm meter and remove the jumper cable
6. Mark base idle screw so that you know if it moves and get a new drill plug for the mixture screw on the AFM

Thanks again everyone for the help and a special thanks to Eric!

[tobbsi]

Hi again everyone,

I have now had some time over to spend on my car. And money! I took a break from the engine issue and spent some time fixing my stuck door locks. They were corroded in place so to speak. Back to the engine. I have now replace to cap, rotor and the spark plug wires. It did much difference. It now sounds much smoother but there were still some misses now and then. Now I didn’t really know what to do so I called a guy that has worked on a lot of 944s and at the moment has my neighbors car to do some suspension work. I had to take the whole story about the engine and some history what had been done to it before. After some thinking and talking about fuel system and God knows what we ended up in a mixture problem again. Here is the thing.. What my small brain didn’t understand before is that the mixture screw on the AFM only corrects CO on IDLE. Not when the throttle is off the TPS idle position! In other words you can lean the mixture out so much that it starts to misfire at times. I thought the mixture was good before because when I buried the pedal in floor it ran good. Obviously Bosch designed this system this way for some reason I don’t know but perhaps the engine needs a bit more fuel at idle to run smoothly? Anyway I turned the screw in a couple of turns and the misfire went away completely and also the engine rpm rose a lot. I corrected the base idle on the throttle body and removed the jumper cable and now it works like charm. The question is how it could have become this way.. I have a receipt from a Porsche dealer where they adjusted the CO after the faulty AFM was replaced so it should have been good! The things is this I believe: Because of the faulty Idle Speed Valve someone had tinkered with the throttle body and therefore the base idle was way to high. Even after I put things right it used to idle at about 1100 rpm. Because the idle was high the dealer had not got the mixture right for the idle. So now that I fixed the ISV and the idle now is back to normal 800 rpm and the base idle set to 840 rpm the mixture is too lean at that engine speed. I am not an expert on this but I believe it must have been something like this. Later on when I’m going to take the car out of the garage and start driving it I will have to take it to a shop with a gas analyzer and correctly set the CO.
For those of you who wonder how to do that:
1. Warm engine up
2. Defeat idle stabilizer (ISV) at diagnostics port
3. Connect a rpm meter to the ignition coil
4. Adjust CO with a gas analyzer in the tailpipe and make sure the base idle is at the right interval of 840 +/-40 rpm ALL the time.
5. When CO is correct and idle is correct disconnect the rpm meter and remove the jumper cable
6. Mark base idle screw so that you know if it moves and get a new drill plug for the mixture screw on the AFM

Thanks again everyone for the help and a special thanks to Eric!

[tobbsi]

Thank you again Eric for replying! And everyone else too ofcourse! I will start with replacing the wires and go from there. I haven’t had time to do much else with the car so i’ll make another post when I know something new. You all take care in the meantime!

[Author]

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