D4D Engine Stops On Traffic Lights

[AveOnPop]

When slowing down to traffic lights etc I push the clutch pedal. 90% of the times the engine idles normally. But from time to time the engine just stops. So, I need to restart :(

Sometimes it starts only barely, fortunately the Battery has not gone totally empty. But it could take couple of tries before it starts.

The issue is only mainly while the engine is warm, but it has happened on cold too.

This has been going on for some months already. I've changed fuel filter, air filter and sparks, cleaned EGR valve and cleaned MAF sensor (well, MAF is not easy to clean completely).

According to dealer the engine does not have separate idle valve. Diagnostics shows no errors, that might be because the problem is not there always.

I'm getting desperate. What might be the problem? Anyone? It's annoying that the engine just stops while idle.

[igormus]

When slowing down to traffic lights etc I push the clutch pedal. 90% of the times the engine idles normally. But from time to time the engine just stops. So, I need to restart :(

Sometimes it starts only barely, fortunately the battery has not gone totally empty. But it could take couple of tries before it starts.

The issue is only mainly while the engine is warm, but it has happened on cold too.

This has been going on for some months already. I've changed fuel filter, air filter and sparks, cleaned EGR valve and cleaned MAF sensor (well, MAF is not easy to clean completely).

According to dealer the engine does not have separate idle valve. Diagnostics shows no errors, that might be because the problem is not there always.

I'm getting desperate. What might be the problem? Anyone? It's annoying that the engine just stops while idle.

hello mate

both SCVs have to be inspected; have you escaped an air from filter/fuel injection system?

Cheers/Igor

[AveOnPop]

Cheers Igor!

Is there a way to check SCVs without any special equipment? I know the location of one of them, where is the other?

When I changed the fuel filter, I pushed the "ball" on the assy as many times as it got hard. You meant that?

While driving the engine works always as usual, it's just the problem with idle.

[igormus]

Cheers Igor!

Is there a way to check SCVs without any special equipment? I know the location of one of them, where is the other?

When I changed the fuel filter, I pushed the "ball" on the assy as many times as it got hard. You meant that?

While driving the engine works always as usual, it's just the problem with idle.

hi

they are (SCV) both on the pump body -- each one's solenoid coil must be measured on resistance by means of multitester or so. as to air escaping -- you did not mention whether or not you ve released an air escaping screw before priming this membrane -- if not the air is still in the system even minor part criating headache at idle.

cheers

Igor

[AveOnPop]

You have a great knowledge! A true Guru

Air escaping screw does not ring a bell. Is there a way to do it afterwards?

However, the problem existed before I changed the fuel filter.

A quote from the service manual:

(a) Check the suction control valve for resistance.

(1) Measure the resistance between the terminals.

Resistance: 1.9 to 2.3 ohm at 20 C (68 F)

Well, it's rather cold in here in Finland right now and I don't have a warm garage. If the temperature is about -10 to 0 C, does it matter?

Does that do the magic?

[igormus]

You have a great knowledge! A true Guru

Air escaping screw does not ring a bell. Is there a way to do it afterwards?

However, the problem existed before I changed the fuel filter.

A quote from the service manual:

(a) Check the suction control valve for resistance.

(1) Measure the resistance between the terminals.

Resistance: 1.9 to 2.3 ohm at 20 C (68 F)

Well, it's rather cold in here in Finland right now and I don't have a warm garage. If the temperature is about -10 to 0 C, does it matter?

Does that do the magic?

ok look -- the resistance must be checked at definite temperature -- the garage does not influence on your attemps -- just hahve both SCV remoned and play with them iin warm place (do not forget to have a tester :) )-- be sure in case actual resistance is out of limits specified then just replace both SCVs. as to an air escaping -- all must be clear for you. Good luck/Igor

[t-spiritpete]

When slowing down to traffic lights etc I push the clutch pedal. 90% of the times the engine idles normally. But from time to time the engine just stops. So, I need to restart :(

Sometimes it starts only barely, fortunately the battery has not gone totally empty. But it could take couple of tries before it starts.

The issue is only mainly while the engine is warm, but it has happened on cold too.

This has been going on for some months already. I've changed fuel filter, air filter and sparks, cleaned EGR valve and cleaned MAF sensor (well, MAF is not easy to clean completely).

According to dealer the engine does not have separate idle valve. Diagnostics shows no errors, that might be because the problem is not there always.

I'm getting desperate. What might be the problem? Anyone? It's annoying that the engine just stops while idle.

Hello, firstly does the engine idle at 1200rpm cold and 800rpm when hot and if you leave the aircon on does the fault still occur? If so it could be one of the sensors like water temp, fuel temp or throttle position sensor playing up, also do you know that the MAF is working 100%? The ECU needs all it's input signals to be correct to suit all given conditions to give the correct output if you catch my drift, any input that's not quite right and and the engine cannot respond correctly when the ECU thinks it has done the right thing.

Best regards, Pete.

[AveOnPop]

Hello, firstly does the engine idle at 1200rpm cold and 800rpm when hot and if you leave the aircon on does the fault still occur? If so it could be one of the sensors like water temp, fuel temp or throttle position sensor playing up, also do you know that the MAF is working 100%? The ECU needs all it's input signals to be correct to suit all given conditions to give the correct output if you catch my drift, any input that's not quite right and and the engine cannot respond correctly when the ECU thinks it has done the right thing.

Hi,

Yes, engine idles 800 rpm normally and 1200 rpm when heating the interiot. To be precise, idle while slowing down and clutch down is about 850 rpm and when the car is stopped the idle goes down to 800 rpm. Aircon does not effect, the problem is there with or without it. I haven´t been able to test the MAF, so I don't really know if it works 100% all the time.

It appears like a heart EKG-film: if you had a heart attack an hour ago, it doesn't show on the film taken now, you need to be having an attack while filming. OK, bad picture, but this is how it seems to me. If there is nothing wrong while running the diagnostics, it looks like there's nothing wrong :(

[t-spiritpete]

Hello, firstly does the engine idle at 1200rpm cold and 800rpm when hot and if you leave the aircon on does the fault still occur? If so it could be one of the sensors like water temp, fuel temp or throttle position sensor playing up, also do you know that the MAF is working 100%? The ECU (ECD) needs all it's input signals to be correct to suit all given conditions to give the correct output if you catch my drift, any input that's not quite right and and the engine cannot respond correctly when the ECU thinks it has done the right thing.

Hi,

Yes, engine idles 800 rpm normally and 1200 rpm when heating the interiot. To be precise, idle while slowing down and clutch down is about 850 rpm and when the car is stopped the idle goes down to 800 rpm. Aircon does not effect, the problem is there with or without it. I haven´t been able to test the MAF, so I don't really know if it works 100% all the time.

It appears like a heart EKG-film: if you had a heart attack an hour ago, it doesn't show on the film taken now, you need to be having an attack while filming. OK, bad picture, but this is how it seems to me. If there is nothing wrong while running the diagnostics, it looks like there's nothing wrong :(

Hello again, I have attached some info on the MAF and intake shutter, if you don't already have it maybe it will help you.

EDIT:- attached more info.

Pete.

[AveOnPop]

Thanks Pete. Actually I already downloaded these files, but thanks for pointing me the right spots :)

Here's an update: after using Webasto for ten minutes the Battery went almost totally empty. It was the original Battery, so I decided to change the Battery.

Bought new this morning, installed it. Keeping my fingers crossed, but the problem has not occured (at least yet...).

Of course, if the problem comes back, I start to do more research, but at the moment it seems OK!

This car has made strange things before: a year ago engine light and TRC light went on. Stability management and TRC went also off (during winter an uncool thing). After code reading: nothing. 50 euros, lights off, thank you! Then the problem came back. Disconnected battery for 30 secs and everything OK. This happened about 200 times. I was totally ****** with my car. Someone told me to change glow sparks (one of them was wet), I did: problem was gone! Come on, what an unlogical thing, if the stability management goes off, just change the sparks!

[t-spiritpete]

Thanks Pete. Actually I already downloaded these files, but thanks for pointing me the right spots :)

Here's an update: after using Webasto for ten minutes the battery went almost totally empty. It was the original battery, so I decided to change the battery.

Bought new this morning, installed it. Keeping my fingers crossed, but the problem has not occured (at least yet...).

Of course, if the problem comes back, I start to do more research, but at the moment it seems OK!

This car has made strange things before: a year ago engine light and TRC light went on. Stability management and TRC went also off (during winter an uncool thing). After code reading: nothing. 50 euros, lights off, thank you! Then the problem came back. Disconnected battery for 30 secs and everything OK. This happened about 200 times. I was totally ****** with my car. Someone told me to change glow sparks (one of them was wet), I did: problem was gone! Come on, what an unlogical thing, if the stability management goes off, just change the sparks!

Hope all goes well after fitting the new Battery it's a good time of year to do it anyway and not just for starting the engine starting as solenoid valves can play tricks when the Battery voltage gets low. If you got the same help from a garage that you are giving your hard earned money to as you do from the members on this forum life would be a lot easier .......... plus they have actually got the vehicle in front of them!

Please let us know the long term result with the new Battery.

Good luck and best regards,

Pete.

[AveOnPop]

Unfortunately the problems are back. Maybe the #times per day has decreased, but nevertheless the car still stops from time to time.

I disconnected the MAF and took it home. The resistance was supposed to be between 2.19 and 2.67. After several measurements the resistance is about 2.08 ohm at room temperature. That should be near enough, right?

Now I need to check if the voltage changes when blowing into the MAF. One silly question: it says "apply Battery voltage across terminals 3 and 4". Should I connect the plus to both of them or plus to one and minus to the other?

Thanks again, you've been great!

[igormus]

Unfortunately the problems are back. Maybe the #times per day has decreased, but nevertheless the car still stops from time to time.

I disconnected the MAF and took it home. The resistance was supposed to be between 2.19 and 2.67. After several measurements the resistance is about 2.08 ohm at room temperature. That should be near enough, right?

Now I need to check if the voltage changes when blowing into the MAF. One silly question: it says "apply battery voltage across terminals 3 and 4". Should I connect the plus to both of them or plus to one and minus to the other?

Thanks again, you've been great!

hi again :)

i am still can not catch you - if both SCVs are in order and been tested?

Cheers/Igor

[AveOnPop]

No Igor, I have not yet get into testing the SCVs. I'm trying to test functionality of MAF first.

Please check the file Pete attached th other day:

Engine control system.gif (56.68K)

[igormus]

No Igor, I have not yet get into testing the SCVs. I'm trying to test functionality of MAF first.

Please check the file Pete attached th other day:

Engine control system.gif (56.68K)

ok

just do not keep silence but have us up-dated.

cheers/Igor

[AveOnPop]

Of course, I'll keep you updated!

Igor, do you know what that means? The thing I asked an hour ago:

"apply Battery voltage across terminals 3 and 4".

Should I connect the plus to both of them or plus to one and minus to the other?

[igormus]

Of course, I'll keep you updated!

Igor, do you know what that means? The thing I asked an hour ago:

"apply battery voltage across terminals 3 and 4".

Should I connect the plus to both of them or plus to one and minus to the other?

OK the Battery has six cells and the voltage is normally taken from a boarder cells (+) and (-) to have a voltage from a full Battery volume. now you should conside two cells belong to Battery and take full voltage criated from them (two cells). but i am thinking how will you take this in cacsce the battery is service free :crutchy: -- let's wait for other posters -- may be i ve explained incorrectly . cheers/Igor

[Thermal]

That should be near enough, right?

No, sorry.

You will have to realize that you are working with very sensitive parts, that have very little margin with the reference model programmed in the ECM/ECU.

The manual says: resistence must be between 2.19 and 2.67 kOhm.

If not, replace the MAF.

You are diagnosing a possible MAF related problem here, so if you measure a value of 2.08 kOhm, it is below the minimum reference value and needs to be replaced.

Repeat the measurement with another Ohm meter at 20 degrees if you like, and if the reading is out again, you may have found the cause of your problem.

Going further down into the diagnostic flowchart when you find a value that is out of spec, is pointless because you will either draw the wrong conclusions or never find the problem. :(

And to your other question:

"Battery voltage" is 12 Volt DC, as you would take from the car's Battery.

Simply connect "+" to one of the terminals and "-" to the other, both as instructed by the manual, blow air into the MAF and watch the voltage.

If the voltage does not fluctuate, the MAF sensor is defective.

[t-spiritpete]

Of course, I'll keep you updated!

Igor, do you know what that means? The thing I asked an hour ago:

"apply battery voltage across terminals 3 and 4".

Should I connect the plus to both of them or plus to one and minus to the other?

Hello again, don't want to step on Igors toes here but anyway you need a 12vdc source near to where you are testing the MAF so maybe bring in a car Battery, your old one will do and make up 2 leads from light guage wire that you can connect to the terminals 3 and 4 as per diagram. It is better to have them connected to the maf first to avoid short circuit from the Battery, it won't matter which is (+) and which is - then connect the multimeter ( set to the DC Voltage range) as shown , (+) probe to VG and (-) probe to EG2. Carefully connect the 2 wires coming from pins 3& 4 on the maf to the Battery terminals (+) & (- )and read the multimeter voltage ..... then blow onto the maf as shown and watch for a variation to the voltage reading this will prove the maf is working.

You should also do the resistance readings later after changing the multimeter over to ohms range.

Just a word of warning ... if you don't you put an inline fuse in circuit do not let the bare ends of the 12vdc supply in the test wires coming from the battery touch together as they will melt in your fingers causing a very very bad burn!! (You don't need the inline fuse if you are very careful).

Come back to me if you don't understand any of this.

Hope this helps ....Pete. !

EDIT ..... sorry Thermal we replying at the same time ....almost!

[AveOnPop]

Hi,

Thanks to all of you!

I'll check the MAF either tomorrow or sunday. I'll update the situation then.

[AveOnPop]

Now, here's an update here after loooong time.

The problems with idle have gone worse. Tester did not give any error codes unfortunately.

MAF is not the guilty one, I suppose. I got this conclusion because I removed the MAF wires from MAF and the problem was still there (engine service light went on -> reset it by disconnecting the battery).

Now I'd like to inspect the SCV's.

I understood there are two of them(?). I can see the one in the pics on this topic, but where's the other?

Thanks!

[Thermal]

MAF is not the guilty one, I suppose....

Sorry, don't want to be rude, but you still don't get it...

You measured a way out of range value of 2.08 kOhm on the MAF (which indicates that you found a- or the problem; the MAF is at fault).

But you ignore that and continue looking for a problem that you do like?

Hmm...

Pulling the wires from a faulty MAF with the engine running doesn't prove anything.

That only turns the Check Engine light on. :(

[AveOnPop]

No fence taken :)

...or maybe I still don't get it (get what?)

I did not pull out the MAF plug while the engine was running.

I pulled it out -> fired up -> went driving (so, the MAF was definately not working at all at that time) -> same problems occured.

This is how I was certain that the MAF was not causing the problem. How come it did not prove anything?

[Thermal]

Because.... it makes no difference if you drive your car with a defective MAF with- or without the wires attached.

In other words, it's defective with- or without the wires attached and therefore you'll notice no difference.

The diagnostics flowcharts referred to above, and from which several members quoted, rely on taking the prescribed action if one of the steps give an incorrect result or an abnormal reading.

In this case: "MAF resistance readings out of spec": --> Replace the MAF, repeat the measurement and if OK, continue with the next step.

"Assuming" such findings are still "a little bit correct", and going to the next step is pointless.

You may never find the real problem and end up drawing the wrong conclusions further down the chart, replacing parts that are not defective, and so on....

In the end, after spending a lot of time and money, you'll give up and turn to a Toyota dealer to get it fixed. :(

These diagnostics flowcharts were specially develloped to rule out the guesswork.!

Use them wisely.

[AveOnPop]

Here's an update:

I borrowed a MAF from my friend's car -> did not help.

I bought and installed a secondhand SCV -> did not help.

Car does not start at all now! When I turn the key it almost starts after two seconds, then the starter only runs but it will not start. If I try to turn the key again, same story. The fuel will not go into the cylinders for some reason.

Now I'm getting desperate since I'm rather short with money and cannot afford to take the car to Toyota service.