HELP!!! I've got a stalling issue that the shop can't resolve.

[speedracer129]

Hey All,

Been having this random stalling issue with my '08 RS4 for months now. Had a carbon clean done about 1 1/2 years ago (20k miles ago). The car is at 034 Motorsports right now and they've had it for awhile and can't figure out what the heck is wrong with it. These were the codes they found most recently (it's been in and out of 034 about 3 times in the last 6 months):

ECM 1:
P1577 - Right Engine Mount Solenoid Valve (N145) - Open Circuit

P0190 - Fuel Pressure Sensor (G247) - Curcuit Malfunction - Intermittent

P2004 - Intake Manifold Flap; Bank 1 - Stuck Open - Intermittent

P1923 - Please Check DTC Memory of ECU Number 2

ECM 2:
P0172 - Fuel Trim; Bank 2 - System Too Lean - Intermittent

They replaced the fuel pressure sensor, flap solenoid, and cleaned out the carbon again. Thought this would do the trick, but it still stalls out! Codes have not returned yet, but it's only been driven 60-120 miles since the sensor, solenoid, and carbon has been dealt with.

Thanks,

Chris

[your daddy]

replace your engine mounts. (hell get the the 034 ones!) and put the resistor in. clear faults. and drive. hopefully. dont think hard about it, just do it.
(I have had the mounts short on other 4.2fsi cars, and they are on the same circuit as the hpfp. on these, the harder you accelerated in the rpm, the slower it went)

[your daddy]

????

[wednesday]

When does it stall? During drive/idle/after warm up/city/highway? Do you end up with epc light as well? When you say stall, does it turn off? Will it turn on right away afterwards?.. trying to understand..

[JimmyBones]

When does it stall? During drive/idle/after warm up/city/highway? Do you end up with epc light as well? When you say stall, does it turn off? Will it turn on right away afterwards?.. trying to understand..

This is very important and helpful information.

Most likely this is fuel related. So either the injectors are not flowing correctly, the fuel can't get to the high pressure fuel pumps correctly because of a clogged fuel filter or the low side pump is dieing, or the high pressure fuel pumps can't build up enough pressure. Most likely in that order of possibilities. It would be very helpful to see the 01 and 11 engine measuring value block readings for channels 103, 106, and 140 at idle, while driving, WOT, and after the engine is shut off a few minutes later.

[your daddy]

does it go slower, the more you push on the gas pedal?

[speedracer129]

It stalls as in completely dies. It doesn't shudder or do anything like that before it stalls. It usually stalls when you pull up to a light and it's in neutral already. It will even stall/die out after completely warmed up. Definitely sounds like a fuel delivery issue, which 034 has checked out. Yes, I did get an EPC light twice right after I started the car. But I just turned off the car and turned it back on and the EPC light goes away. The EPC light rarely comes on. But say at highway speeds, it won't stall out though if you're cruising slightly below 3K RPM, it feels like it would stall if it weren't in gear, because you kind of feel it hesitate a little. If you're cruising along above 3K RPM, it feels normal.

[Velox]

Did they check the fuel pressure at shop?

[speedracer129]

Did they check the fuel pressure at shop?

Yes, supposedly the values came back normal. They are going to try to replace the crank position sensor at this point and see what happens. I also have them testing the PCV to see if it is leaking or anything.

[ven0m]

Is the CPS a transmission-out job, or can it be done from underneath the car?

[badbluers4]

Ahhhhh this is an easy one. It's the updated relays. I forgot the number. I had this same issue last year and replaced them, and problem fixed. I'll find the details in one sec.

[JimmyBones]

Is the CPS a transmission-out job, or can it be done from underneath the car?

Can be done underneath after disconnecting the connector under the coolant tank. Actually the transmission will not come off easily unless the CPS body is removed. We had a few techs break CPSs from that mistake while trying to replace clutches.

[badbluers4]

It's the updated 614 relays. They are in the ECU case on the driver's side. Have to remove the driver's side wiper to access them. But the car will drive good as new again. Audi updated these relays and they control fuel pump if I'm not mistaken.

[simple_king]

It's the updated 614 relays. They are in the ECU case on the driver's side. Have to remove the driver's side wiper to access them. But the car will drive good as new again. Audi updated these relays and they control fuel pump if I'm not mistaken.

What's the part number on those relays?

[badbluers4]

4HO-951-253

[speedracer129]

Sweet! So after you swapped out those 614 relays, your stalling issues went away? Looks like an easy fix! Thanks!

[ven0m]

Can be done underneath after disconnecting the connector under the coolant tank. Actually the transmission will not come off easily unless the CPS body is removed. We had a few techs break CPSs from that mistake while trying to replace clutches.

Thanks for the heads-up Jimmy! Getting ready for my first clutch job. (And off goes the front subframe with the solid bushings again)

@OP, did you try the fix with the relays that Blue suggested?

[speedracer129]

I will try the relays and get back to you! My car is currently at 034 Motorsports in Fremont, CA and I have forwarded them this thread. Hope it works. Thanks!

[badbluers4]

I will try the relays and get back to you! My car is currently at 034 Motorsports in Fremont, CA and I have forwarded them this thread. Hope it works. Thanks!

Yeah no prob. Hopefully it works out. Your symptoms and codes sounds very similar to mine. When it stalls, do you have to wait like 30 secs to restart it? and even rolling start won't work? That's how mine worked. Ever since the new relays, I've had zero issues.

- - - Updated - - -

Sweet! So after you swapped out those 614 relays, your stalling issues went away? Looks like an easy fix! Thanks!

Yes sir! Never looked back. Been over a year now. And this stalling issue went on for some time (maybe a year) and it gradually got worse.

[dturn37]

I actually had the same issues when I had my RS4. The car kept dying and would throw a ton of fault codes. It was gradually getting worse and as a last ditch effort I swapped out the relays that badbluers4 suggested. The problem never came back for a year until I traded it in for the 1M. Hope thats the problem!

[badbluers4]

I actually had the same issues when I had my RS4. The car kept dying and would throw a ton of fault codes. It was gradually getting worse and as a last ditch effort I swapped out the relays that badbluers4 suggested. The problem never came back for a year until I traded it in for the 1M. Hope thats the problem!

Wow yeah. These relays should probably be a sticky on this forum. They are such a pain, but such an easy fix!

[speedracer129]

Yeah no prob. Hopefully it works out. Your symptoms and codes sounds very similar to mine. When it stalls, do you have to wait like 30 secs to restart it? and even rolling start won't work? That's how mine worked. Ever since the new relays, I've had zero issues.

- - - Updated - - -



Yes sir! Never looked back. Been over a year now. And this stalling issue went on for some time (maybe a year) and it gradually got worse.

Oh wow, I didn't have to wait like 30 secs to restart though. Like for example, I'd hit traffic and have to come to a stop... I'd put it in neutral and it would just die out. I would be able to immediately turn it back on to keep going as the traffic moved. I am awaiting the results of changing the relays. Despite the slight differences in our symptoms, I hope we have the same problem! Thanks again.

[badbluers4]

Oh wow, I didn't have to wait like 30 secs to restart though. Like for example, I'd hit traffic and have to come to a stop... I'd put it in neutral and it would just die out. I would be able to immediately turn it back on to keep going as the traffic moved. I am awaiting the results of changing the relays. Despite the slight differences in our symptoms, I hope we have the same problem! Thanks again.

No prob. Yeah keep us posted!

[speedracer129]

No prob. Yeah keep us posted!

Good news to report!!! Got my car back from 034 Motorsports last Friday and they did replace the relays and did a road test. Car was fine. So I took it home and she was running great. Since they had the intake manifold off for the fuel pressure sensor, I just had them do a carbon clean too. Anyhow, I drove the car a lot over the weekend and throughout this week... street driving, highway, stop and go traffic, etc... hot weather and warm weather.

Things to note:

-In neutral at idle, the RPMs used to fluctuate slightly while the car was just sitting. This NO LONGER happens.

-Sometimes if you were cruising around in gear below 3K RPMs, you could feel a little hesitation if you lifted off the gas (as if it would have stalled out had you not been at 2K+ RPMs. I haven't felt this at all anymore.

So after one week, everything seems back to normal! Many thanks to BadBlueRS4 for the tip on the relays! Had you not suggested that, 034 Motorsports was ready to throw in the towel and send me to the stealership. If you've ever in California, I'd love to buy you a drink!

[ven0m]

Good to hear!!

[badbluers4]

Good news to report!!! Got my car back from 034 Motorsports last Friday and they did replace the relays and did a road test. Car was fine. So I took it home and she was running great. Since they had the intake manifold off for the fuel pressure sensor, I just had them do a carbon clean too. Anyhow, I drove the car a lot over the weekend and throughout this week... street driving, highway, stop and go traffic, etc... hot weather and warm weather.

Things to note:

-In neutral at idle, the RPMs used to fluctuate slightly while the car was just sitting. This NO LONGER happens.

-Sometimes if you were cruising around in gear below 3K RPMs, you could feel a little hesitation if you lifted off the gas (as if it would have stalled out had you not been at 2K+ RPMs. I haven't felt this at all anymore.

So after one week, everything seems back to normal! Many thanks to BadBlueRS4 for the tip on the relays! Had you not suggested that, 034 Motorsports was ready to throw in the towel and send me to the stealership. If you've ever in California, I'd love to buy you a drink!

Haha!! I'm so glad to hear this!! Trust me I can feel how happy you are! I lived with this stalling issue for about a year and it eventually got much worse and it really freaked me out. Thanks to Blake (Koolade on here) for telling me about the relays too. I was so releaved to have her running smooth again.

On a side note, admins we should make this a sticky!

[VinnysS4]

Yes, supposedly the values came back normal. They are going to try to replace the crank position sensor at this point and see what happens. I also have them testing the PCV to see if it is leaking or anything.

Let me get this right..... they were just "throwing parts at it" in hopes to fix it? Thats not good business practice. I would never take my car to a shop that does this.... juat saying

[speedracer129]

Let me get this right..... they were just "throwing parts at it" in hopes to fix it? Thats not good business practice. I would never take my car to a shop that does this.... juat saying

Hey Vinny, actually that's what they didn't want to do. I had some codes for the fuel pressure sensor, so that was replaced. The problem still persisted after that. They did a bunch of testing and troubleshooting on their own, but did not charge me for it. It is true though that until BadBlueRS4 suggested it was the relays, they didn't know what was going on. After they replaced the relays, one of the techs - who is originally from Alaska - recalled that they used to have to change relays on cold weather cars for similar reasons. Being that we're in California, that didn't come to mind. My crank position sensor and PCV valve was not replaced at this time.

But yeah, thanks for your concern. 034 definitely worked with me through this and it took awhile, but I'm glad for the replies on this post as it ultimately solved my problem. As soon as I told them about the relays, they said we should definitely try that. They were hesitant to go in and change the CPS and PCV.

Regards,

Chris

[MMMB00ST_A4]

Audizine FTW. Good to see the community still going strong.

[speedracer129]

Audizine FTW. Good to see the community still going strong.

Definitely!!! I appreciate all the help fellas.

[badbluers4]

Definitely!!! I appreciate all the help fellas.

I forgot, I'll hit u up for that beer when I make it to San Jose/San Fran! LOLLLLLL

[badbluers4]

I'm gonna report this post to trigger the admins to please make a sticky...otherwise other people will continue to throw parts at their car for no reason LOL

[speedracer129]

I forgot, I'll hit u up for that beer when I make it to San Jose/San Fran! LOLLLLLL

For sure, I'm good for it!

[speedracer129]

For sure, I'm good for it!

Man, you won't believe it... but after a couple months of flawless performance, my stalling problem is back. I had left the car sitting at idle after driving it on the freeway for about 35 minutes. The idle started fluctuating and struggling to hover around 600 RPM. Then, I tried to rev it up and it would just stall out and not hold idle at all. Any ideas?

[your daddy]

rescan it.

[lil98civi]

Anywhere to order the updated 614 relays from? Can't seem to find them

[ixi_ixi]

Man, you won't believe it... but after a couple months of flawless performance, my stalling problem is back. I had left the car sitting at idle after driving it on the freeway for about 35 minutes. The idle started fluctuating and struggling to hover around 600 RPM. Then, I tried to rev it up and it would just stall out and not hold idle at all. Any ideas?

I used to have similar stalling problem you are describing on my RS4. The way it stalled was almost like I forgot to press down the clutch when the car came to a stop (obviously the clutch was depressed but it still stalled). And every time the stalling only happened when the car was slowing down to almost a complete stop ( at red light or 3 point turns/U turn etc). However, I got no fault codes from my scan at all. And when I idle the car for longer than 15 mins or so, the idle will fluctuate like you described. At that time, I also have a slight leaking HPFP.

The first thing I did was I changed the MAF sensor to a new one and the stalling issue went away. However, 3 months later after I changed the MAF, I also changed the HPFP, used high concentrate Audi G17 fuel additive (to clean the injectors as the long term fuel trims are quite uneven between bank 1 and bank 2). And recently I have carbon clean, 8 x new injectors installed, high pressure fuel valve and high pressure fuel sensor replaced, cleaned the throttle body, installed carbon "hot air" intake, gutted pre-cats etc. The stalling problem haven't come back since but as you can see, I did a lot of things in between so that might be a combination of fixes.

May be worth a try on the MAF and cleaning the throttle body?

[Jretal]

Anywhere to order the updated 614 relays from? Can't seem to find them

Just google the p/n. There are a slew of providers. I picked up a pair from Europa parts for $12 a pop. More of a PITA to get to than anything else (and why I'm replacing my as preventative since I have the ECU, etc. out already for the motor R&R.

[speedracer129]

I used to have similar stalling problem you are describing on my RS4. The way it stalled was almost like I forgot to press down the clutch when the car came to a stop (obviously the clutch was depressed but it still stalled). And every time the stalling only happened when the car was slowing down to almost a complete stop ( at red light or 3 point turns/U turn etc). However, I got no fault codes from my scan at all. And when I idle the car for longer than 15 mins or so, the idle will fluctuate like you described. At that time, I also have a slight leaking HPFP.

The first thing I did was I changed the MAF sensor to a new one and the stalling issue went away. However, 3 months later after I changed the MAF, I also changed the HPFP, used high concentrate Audi G17 fuel additive (to clean the injectors as the long term fuel trims are quite uneven between bank 1 and bank 2). And recently I have carbon clean, 8 x new injectors installed, high pressure fuel valve and high pressure fuel sensor replaced, cleaned the throttle body, installed carbon "hot air" intake, gutted pre-cats etc. The stalling problem haven't come back since but as you can see, I did a lot of things in between so that might be a combination of fixes.

May be worth a try on the MAF and cleaning the throttle body?

Thanks for the advice! Will definitely check out the HPFP and MAF. They checked my injectors last time and they seemed ok and I just did a carbon clean too. Finally got to take the car into 034 Motorsports and they found a code regarding the "idle control system." My service advisor didn't give me the specific code, but as soon as I get it, I'll post it up here.

Thanks again!

[speedracer129]

Ok, stalling is back. Brought the car in to 034 and there was a code for the throttle body. Got the Corvette throttle body because it’s the same part, only cheaper.

Got car back and kept stalling and fluctuating at idle. Brought back to 034 to check the relays because in between all this, Ed told me the replacements for the 614 relays were green 644 relays.

Had 034 Check then again and it turned out old tech (now gone) had put in aftermarket relays that were supposedly black in color.

They apologized, supposedly got the right relays and put them in. Car drove good after that.

Now, been driving the car for 5 days straight commuting and all was good. Today, it just stalled at a light when I came to a stop. Got it started again, but idle was fluctuating again.

Revved it up a bit, pulled into a lot and let it sit for 3-5 mins. No fluctuations this time.

I haven’t looked into the MAF or high pressure fuel pump yet. This is driving me nuts!

Thanks.