Intermittent no crank - need ideas (pics within)

**wbrunner23** · 03-23-2014 03:32 PM

*Starter replaced - so far, so good*

My 2001.5 6spd Avant has been bitch lately - intermittent no crank. All lights on dash light as expected, but when I turn the key...nothing - starter is not engaging - literally no noise other than clicking under-dash relays.

Go to start the car the other day and no crank. Bypassed clutch switch with with paperclip, but no go.

Replaced battery (was weak). It started a few times, but inconsistently.

Replaced ignition switch (Genuine OEM switch). Nothing on first 3 tries, fires up on 3rd. Since new ignition switch, it crank & starts sometimes, other times starter jumps in for a second then cuts out - no start, and other times there's nothing - no starter, no noises, no blinking lights, etc.

The battery voltage is up above 12v on the instrument cluster. The car will start up a run fine by popping the clutch. All fuses on driver side door jam checked good. No codes via VAGCOM.

Anybody ever experienced symptoms like this before? I'm lost on this one.

Before I dig into a starter replacement, I want to explore relays. Can't find much info in my Bentley, so hoping for some help identifying the relays for possible cause of no crank/intermittent no crank.

389 - intermittent wiper
372 - fuel pump
370 - wipers, turns signals, etc.. ?
53 (left) - horns?
53 (right) - ?
267 - A/C clutch module?
387 - ?

I feel like the panel further back is related to accessories and other things that should be causing a no crank/no start condition, but I could be wrong.

373 (left) - ?
373 (right) - ?
382 - ?
4 fuses below - ?

Thanks guys. Really need help here, this is incredibly frustrating. I've already taken the car to the dealership for diagnosis, but the intermittent no crank decided to hide so the tech didn't find anything wrong.

**rdcyclist** · 03-23-2014 03:55 PM

I can't comment specifically but in general troubleshooting, relays are rarely, in my experience, intermittent. Connections on the other hand...

I've probably got more years troubleshooting this shit than you've been on earth. That doesn't mean I'm right, it just means I've done this a time or two. Just not with the B5 S4 but they're not that much different from any other car. Much...

Here's the sequence I would use:

1. Make sure your battery terminals are clean and making good connection. Check them with a meter on voltage from the battery to the cable. Should be minimal voltage drop.
2. Grounds. Make sure all the ground cables are well connected. A visual might be good but putting a meter across the connection and cranking will tell you more.
3. Hot lead to the starter. Loose nut at the solenoid will give your symptoms.
4. Trigger lead to the solenoid on the starter; this is what tells the starter solenoid to kick out the starter pinion and sends the big current to the starter motor. Make sure it's not loose and the wire's not broken. Put a meter on it and have someone turn the key to the start position. Should be seeing 12 volts every time. If it is, you gotta bad starter and/or solenoid. The starter is enough of a pain in the ass to change, just replace the whole thing. I'd probably do the alternator then too but that's just me; I hate replacing that bitch so if I'm in there.
6. If there's not 12 there, make sure the wire's good. That little wire sees a lot of heat from the turbo and exhaust and the jacket will get brittle and then cause the wire to break. If I was a betting man, that's where my money would be.
5. If the wire's good and you're not seeing 12 at the trigger then you've got a crab grass problem. That's when you start foolin' around with the relays and crap under the dash. I'm pretty sure the problem's elsewhere but we are talkin' B5 S4's here...

Good luck and keep us informed how it goes.

**zillarob** · 03-23-2014 06:10 PM

Early or late car?
On the late there is a single wire connector on the pass side firewall near the o2 connectors. Should be a red w/black stripe or vice versa.
You can test for 12v here to see if everything in the car is doing its thing. You can also shoot 12v straight to the starter.
If early, its similar, but i think its a 2 wire connector.

**wbrunner23** · 03-24-2014 06:21 AM

rdcyclist - thanks for taking the time to write that up. Very helpful

. Time to get the multimeter out.

zilla - it's a late car so I will check that wire to make sure its seeing power. Would I have to peel back some of the insulation? That wire is part of the loom that runs down below the air box to the alternator/starter (right?), so I'm guessing I would have to open it up a bit to get a reading.

Do you guys know if I can access the starter w/ my multimeter from underneath or if I will I have to pull the front clip? If I can access from underneath, I should be able to get some readings tonight after work.

Honestly, I should have been thinking starter already, but I was trying to avoid it. I was hoping a quick relay swap would be all she needs, but I should know better at this point

.

I had the engine out for stg3 goodies last June and the trans out last month for a failed SPEC pressure plate (replaced with a Southbend Stg3 Endurance with organic/feramic disc over standard Kevlar disc - it feels soooooo much better than the SPEC unit). I am going to guess that something worked itself loose when I was jiggling the starter back and forth to drop the gear box. It was the ~month of problem free start-ups that had me second guessing the cause.

**zillarob** · 03-24-2014 10:59 AM

Originally Posted by wbrunner23

zilla - it's a late car so I will check that wire to make sure its seeing power. Would I have to peel back some of the insulation? That wire is part of the loom that runs down below the air box to the alternator/starter (right?), so I'm guessing I would have to open it up a bit to get a reading.

Dont have to peel anything back, it is a connector clipped to the firewall right behind the maf housing.
Cant really get to the starter, so one side goes to the starter, the other to everything else in the car.

**rdcyclist** · 03-24-2014 11:24 AM

Yeahbut he's gonna hafta get to the starter if there's 12v at the firewall connector and the car isn't starting. I think to get at the solenoid connection at the starter, you gotta remove the turbo outlet plumbing. It's not a pleasant task.

**wbrunner23** · 03-24-2014 12:06 PM

So, I did some searching and found this: http://www.audizine.com/forum/showth...tart-issues%29

For the B6, but idea should be the same. I can at least rule out switches by jumping the starter directly off the battery. What do you think zilla?

Other than that, I'm gonna try to fit my multimeter up to the solenoid. If that doesn't work (probably won't), I'll be pulling the starter. I would like to bench test the starter, but it would be nice to have a new one on hand in case.

This rebuilt Bosch starter isn't bad price-wise, but do I have to worry about compatibility issues? ECS says something about checking your part # before ordering. http://www.ecstuning.com/Audi-B5_S4-...tarter/ES1875/

**wbrunner23** · 03-24-2014 12:13 PM

Originally Posted by rdcyclist

Yeahbut he's gonna hafta get to the starter if there's 12v at the firewall connector and the car isn't starting. I think to get at the solenoid connection at the starter, you gotta remove the turbo outlet plumbing. It's not a pleasant task.

I'm not really looking forward to the job, but after pulling my trans outside on jack stands in the middle of the NE Winter we are having this year, a starter job should be a breeze

**AudiSportB5S4** · 03-24-2014 12:55 PM

Have you ruled out your crank position sensor yet? My buddy had the same thing, very intermittent starting issues and it was solved when he replaced the CPS.

Here's his thread... Almost the same title lol

**Monty23** · 03-24-2014 01:18 PM

Originally Posted by AudiSportB5S4

Have you ruled out your crank position sensor yet? My buddy had the same thing, very intermittent starting issues and it was solved when he replaced the CPS.

Here's his thread... Almost the same title lol

I highly doubt the car would pop start and run properly if the CPS was flaking out...

How many miles on your starter?

**wbrunner23** · 03-24-2014 02:00 PM

Well, I just replaced my CPS w/ a brand new Bosch sensor (Chinese manufactured - http://www.ecstuning.com/ES1874/) so it has been in the back of my mind. The old one was destroyed when my SPEC pressure plate failed and shards of metal scored my bell housing. I would imagine that it would at least crank if the problem was the CPS. I checked S4UCE's thread and he said his engine would crank, just wouldn't fire.

It runs great when it decides to start or when I pop the clutch, like Monty said.

The starter is original and I'm just a tick over 130k on the clock. Only times it's been touched were last June during engine pull and last month for trans pull. 2 weeks of issue free driving after trans re-installed, but that didn't last. To top it off, I just finished clutch break in and was ready to start having some fun

**Monty23** · 03-24-2014 02:10 PM

from SSP 941003 -engine management system

The Motronic ECM recognizes a missing [Crankshaft Position] signal after 5 seconds of cranking or engine operation, as well as Short to Battery + and Ground. Should the signal fail after the engine has been started, the engine will continue to run, based on the internally calculated cylinder signal after engine start.

If the Motronic ECM does not recieve this signal, the engine will not start.

I would assume based on this information that if you pop started your car and it was possible to start it this way (sound like this is not possible with a bad CKP sensor from the info above), you should still get a stored code if the crankshaft position sensor was actually bad.

**tambat** · 03-24-2014 03:25 PM

i had a very similar issue on my s4 a while ago (intermittent starting issues, clicking noise).. went through pretty much everything before realizing it was a bad ground. check your grounds!

**james 408** · 03-24-2014 03:39 PM

One more idea: Clutch petal sensor going bad?

**Dorny1** · 03-24-2014 04:15 PM

check the clutch pedal sensor, theres 2 of them...no idea why, I had issues with mine moving around and sometimes not being engaged causing the car not to start. Sounds exactly what i had going on. Take off the bottom of the dash and its up there. I moved mine for awhile, but after having to mess with it when it was below zero i just jumped the connector and now i just have to make sure the clutch is engaged or at least out of gear. but old habits die hard for anyone that drives a stick.

I will bet you 6 internetz its the second clutch sensor on the clutch pedal

**zillarob** · 03-24-2014 04:22 PM

You are on the right track wb.
If you have consistent 12v to one of the plugs on the firewall, that rules everything upstream (clutch sw, ign, etc) out.
If you put 12v to the other connector and the starter works intermittently (or not at all), time to dig deep.

**wbrunner23** · 03-24-2014 04:39 PM

Originally Posted by zillarob

You are on the right track wb.
If you have consistent 12v to one of the plugs on the firewall, that rules everything upstream (clutch sw, ign, etc) out.
If you put 12v to the other connector and the starter works intermittently (or not at all), time to dig deep.

Thanks for the comments guys!

Looks like I'm at the "dig deep" portion of my no crank diagnosis.

Pulled out my multimeter and tested the battery - 12.36v
Pulled the single wire connector on the PS firewall and read voltage while my lady pressed clutch and tried to start - 12.21v
So, I tried to jump the starter straight from the battery and to the other side of the connection and...

...nothing

Looks like I will be pulling my starter. Plan is to bench test (maybe a loose connection at the solenoid or something, IDK), but if not it looks like a new starter. Either way, it seems like the car is sending the signal (and I jumped the signal) but the starter doesn't want to play.

Are there any possible compatibility issues with the starters for our cars? I was looking at this Bosch starter, but am open to suggestions. Maybe a better starter/price out there?? I want to order something now so I have it on hand when I dig into the repair.

http://www.ecstuning.com/Audi-B5_S4-...tarter/ES1875/

**zillarob** · 03-24-2014 04:50 PM

Grim.

Might 2x check the ground for shits and giggles, even add another temporarily.

After that, I would look for a local starter/alternator repair shop.

**xhackerekx** · 03-24-2014 04:53 PM

$255 no big deal this price included core charge after return u old real price is only $190 + shipping around $15 and u no have worry for next 10 years, when u still have car

**rdcyclist** · 03-24-2014 05:47 PM

Did you jump it at the starter or at that firewall connector? That would be step 4.

I'm still betting on a bad wire between that firewall connector and the connection at the starter.

Actually you can test that wire without crawlin' around on the ground. Take you meter and check the resistance (ohms) between the firewall connector and ground. S/B around 5 ohms. If it's not, then either the solenoid is blown (unlikely) or the wire's done broke.

**Monty23** · 03-24-2014 09:19 PM

Bench testing the stater without any resistance isn't going to tell you much if it does rotate.... This test will only really tell you if the starter is completely dead or not. Generating enough torque to free spin vs. to turn a motor is quite different.

**wbrunner23** · 03-25-2014 07:16 AM

rdcyclist - I tried to get a resistance reading between that starter connection at the firewall and the negative battery terminal, ground, & frame rail but got nothing. This could be due to a bad wire/solenoid or because I am basically learning how to use this multimeter as I go (unfortunately, my first real multimeter experience was yesterday w/ voltage readings I posted above).

You make a good point, Monty, without torque for the starter motor to push against, a bench test isn't going to tell me very much about the motor's strength.

I went ahead and ordered a new starter. I found a better deal through Amazon (using my lady's Prime for free 2-day shipping) w/ no core charge. Should deliver by Thursday, so I can hopefully install on Friday. I will be sure to check all wires/connections along the way.

Thanks for all the comments guys. I will report back after the work is done.

**zillarob** · 03-25-2014 10:10 AM

You on it wb, either a bad connection to the starter, or the solenoid coil is borked.

**wbrunner23** · 03-26-2014 06:16 AM

Popped the clutch this morning to move my car to avoid a ticket from parking authority jerks and decided to take her to work. An hour of driving back roads between 3k - 6k and the car drove beautifully. I figured it was good for the battery to get some love from the alternator anyways since it's been sitting. Parked on the ramp portion of the parking garage to aid in popping the clutch to get home tonight.

Turned it off and tried to start the ignition to rule out cold vs. warm start - no crank. New starter on track to deliver tomorrow and install on Friday

**wbrunner23** · 03-26-2014 05:29 PM

Update: Car started under its own power today after work. Drove same ~1 hour of back roads awesomely. Parked, turned off ignition, and car started back up again under its own power. Waited 30 minutes and car started itself under its own power again. So odd.

Anyway, starter job still planned, but does that sound like loose connection or bad solenoid? I'm leaning towards solenoid.

At least it's consistent - consistently bad or consistently good

**Monty23** · 03-26-2014 06:07 PM

When a starter typically goes bad, the brushes wear out and only certain areas will provide enough contact to get the starter turning. What you can try if the car decides not to start again is continuously turn the ignition to the fully off position and try to start the car. I have had to do this up to 60 times with my inlaws hyundai due to a failing starter, but it would eventually start.... This still sounds like a bad starter to me.

**S4gasm aka LOTR** · 03-26-2014 06:31 PM

My guess is starter too. Next time the car does not start, take a hammer and smack the starter real good. Then see if the car starts, if that works, then it's def your starter.

**S4 00 2.7** · 03-26-2014 06:48 PM

Originally Posted by xhackerekx

$255 no big deal this price included core charge after return u old real price is only $190 + shipping around $15 and u no have worry for next 10 years, when u still have car

+1 new starter = no more worries

wb I'm curious, how many miles on your car?

**rdcyclist** · 03-26-2014 06:57 PM

Originally Posted by wbrunner23

Update: Car started under its own power today after work. Drove same ~1 hour of back roads awesomely. Parked, turned off ignition, and car started back up again under its own power. Waited 30 minutes and car started itself under its own power again. So odd.

Anyway, starter job still planned, but does that sound like loose connection or bad solenoid? I'm leaning towards solenoid.

At least it's consistent - consistently bad or consistently good

I'm leaning to the bad wire. The lack of resistance from the connector at the firewall to ground indicates either an broken wire or an open in the solenoid. The solenoid is essentially an electromagnet that gets triggered by the application of 12v to one end of a coil. If that coil opens, it rarely fixes itself. The typical solenoid failure is the part that the electromagnet pulls on getting stuck. Then you've got an intermittent start condition. The wire can get flexed back and forth and make connection or not. That's still my bet.

We should start a pool. It would be way more interesting than college b-ball...

**oppositelock** · 03-26-2014 09:04 PM

Originally Posted by S4gasm aka LOTR

My guess is starter too. Next time the car does not start, take a hammer and smack the starter real good. Then see if the car starts, if that works, then it's def your starter.

If only you could get a hammer in there!

**wbrunner23** · 03-27-2014 06:27 AM

Originally Posted by S4gasm aka LOTR

My guess is starter too. Next time the car does not start, take a hammer and smack the starter real good. Then see if the car starts, if that works, then it's def your starter.

My neighbor, Pork, recommended this. If only there were space...

And yes, Pork looks like you would imagine.

**wbrunner23** · 03-27-2014 06:28 AM

Originally Posted by S4 00 2.7

+1 new starter = no more worries

wb I'm curious, how many miles on your car?

just a hair over 130k. Stg 2 since 60k. Stg 3 since 123k - on second clutch since Stg3

**wbrunner23** · 03-27-2014 06:40 AM

Update: Car started this morning on 3rd try. First try - nothing. Second - small clunk like the starter wanted to play. Third - starter engaged solid. It's always strong when it does crank.

I'm happy it started this morning because I happened to fall behind a Dolphin RS4 for my usual ~1hour of twisties. As far as I could tell, the RS4 had exhaust and man, did it sound sweet! I just cracked the windows and turned the music down. The RS4 really handles itself well on back roads. I have a fair amount of suspension work and it took extra attention to stick with him at points. It was mostly relaxed/slightly spirited driving, but we had a few full throttle corner exits that were a lot of fun. My commute does take me onto a highway towards the end and we did short 2-3rd gear pull. I was gaining on him from what I could see through the thick clouds of carbon from his exhaust (exaggeration). We started to catch up to traffic and he kept blasting but I held off partly because I would be in his backseat if I stayed on it.

We will see if the ol' girl starts on her own after work today. New starter is out for delivery today and should go in tomorrow. I'll keep ya posted.

**zillarob** · 03-27-2014 07:56 AM

If it doesnt, the best way to juice it is hold the key to start and work the clutch (if you havent bypassed the switch down there).

**wbrunner23** · 03-28-2014 06:24 AM

Since it was supposed to rain for the entire day today, I tackled the starter replacement yesterday after work. From start to finish took me about 3 hours and it wasn't all that bad. The worst part was wrestling the alternator back into position - and I spent probably a half hour doing just that.

It has started flawlessly since and the new starter sounds like its got a turbo of its own - takes a second to spin down after the engine fires, haha. Time will tell if my issue is fixed for good, but I feel optimistic about it (can never be sure with the ol' B5).

No what to do with my core??? No core charge through Amazon.