B6A4 Refuses to Start

[senecak]

My B6A4 is refusing to start and I haven’t the slightest idea where to begin. Here’s everything I know:
• Engine cranks just fine; just doesn’t fire until half a dozen or more attempts. The colder it gets the more I have to turn it over to get it to start. Could be the problem is worsening or it could be because the outside temperature has dropped below freezing. Example, this morning was 25 degrees; it took 26 attempts to get it to fire. If I let it sit overnight, I have to crank it several times. If I park it for a few hours, maybe once or twice.
• The engine idle speed is not normal. When it does finally start, it starts at the normal 800 or so RPM’s. It used to climb to 1200-1400 or whatever, then idle down to its normal idle. As a result, it stalls several times before it actually maintains idle speed.
• Once running, its 100% normal (no misfires). Jump on the gas and it pulls with no hesitation. I can drive it through town or on the highway and its fine.
• Mileage is the same as it always has been
• There’s no white smoke coming out behind me the car.
• I don’t own a VAG tool, but the car has no check engine lights on in the dash.
• Car has 188,000 miles on it. Still refusing to part with it. 

As far as I have read, I should check the following:
• MAF sensor. Myabe disconnect it and see if it starts ok???
• Engine Speed sensor???
• IC hose. Not sure what this is???
Anything else I should check or test?

~ Before someone chimes in with the immobilizer... I swapped keys and it didn't help at all.

Appreciate everyone's advice.

[SleeperAvant]

Wonder what spark plugs you have in there? I used to run colder plugs in the summer, but overnight in the Fall / Winter months they would refuse to fire.

[senecak]

I believe their Denso plugs. I put them in at 110,000, so its very possible one or more are fouling up.

[naysay15]

Crank sensor is shot.

[lyates1987]

I would replace plugs and get a new engine crank sensor. 15 minute job.

[Nollywood]

Possible CTS (Coolant Temperature Sensor) is on its way out. Insufficient cold start enrichment.

[old guy]

Possible CTS (Coolant Temperature Sensor) is on its way out. Insufficient cold start enrichment.

Your symptoms point to this ↑

The low idle on start up is normal once the temperature drops close to freezing.

[coffeysm]

How old is your battery? I would start with the basics and have it load tested and see what your current CCA is at.

You can do a resistance test on the crank sensor to see if it's bad. For 3.0 B6 the values should be 730-1000 Ohms depending on the temperature between pins 2 and 3. Pins 1-2 and 3-1 should both read no continuity.
Do your RPMs jump when it cranks and doesn't start? If they do that usually means the sensor is working and if you have a bad sensor, I believe you won't get spark either.
CTS can cause no start condition as well.

[senecak]

Thanks guys. Battery is fairly new. A year old Interstate Battery. Thank god, else I don't think I would've made the 26 attempts this morning.

As for the RPM's. When I turn the key, the engine turns over normally.... just feels like it has no spark or no gas. Then after the umpteenth time, it shows a glimmer of hope. A few more attempts and it starts with the RPM's slowly sputtering to 800 where it finally levels out. Its a rough climb to 800 though... sounds it wants to stall until it reaches 800.

I'll order plugs, coolant sensors (both) and crank sensor. Their all cheap enough.

Thanks for the help guys!!!

[Nollywood]

If you're ordering both sensors, fit just one first, get your ECM scanned, clear any codes, then try starting the engine Start with the cheaper sensor - in this case, the CTS.

There's nothing more frustrating, than fitting a bunch of parts, then finding the engine starts as it should, but...you're none the wiser what the issue was, and what cured it.

[blitz2190]

Thanks guys. Battery is fairly new. A year old Interstate Battery. Thank god, else I don't think I would've made the 26 attempts this morning.

As for the RPM's. When I turn the key, the engine turns over normally.... just feels like it has no spark or no gas. Then after the umpteenth time, it shows a glimmer of hope. A few more attempts and it starts with the RPM's slowly sputtering to 800 where it finally levels out. Its a rough climb to 800 though... sounds it wants to stall until it reaches 800.

I'll order plugs, coolant sensors (both) and crank sensor. Their all cheap enough.

Thanks for the help guys!!!

if your seeing the rpm's move its most likely not your crank senor as Nollywood said your symptoms point to a CTS on its way out.

[senecak]

Define move. It starts and makes it to say 400-500... then slowly creeps to 600, 700... and then normal idle speed where the car finally settles in and sounds and runs normal.

It USED to start... climb right to 1200 or so and then idle down to 800.

[old guy]

Define move. It starts and makes it to say 400-500... then slowly creeps to 600, 700... and then normal idle speed where the car finally settles in and sounds and runs normal.

It USED to start... climb right to 1200 or so and then idle down to 800.

As I previously mentioned the cold start RPM is temperature dependant. Clicky click®

The rear CTS is the one the ECM uses for fueling. That is the one that can cause cold start issues. The CTS in the lower radiator doesn't affect the fueling.

[coffeysm]

Define move. It starts and makes it to say 400-500... then slowly creeps to 600, 700... and then normal idle speed where the car finally settles in and sounds and runs normal.

It USED to start... climb right to 1200 or so and then idle down to 800.

I meant if it moves at all. If you crank the car and it doesn't start the RPM needle should still jump up. I'm pretty sure if your crank sensor was bad/on the way out the needle would stay at 0 during those times. I would start with the CTS first like some other people have mentioned and you can always do a resistance check on the crank sensor, it would be easier/cheaper vs. taking it out and replacing it.

I wouldn't just throw parts at it, I would try diagnosing the problem first. My car had a start issue that all pointed to fuel delivery and it ended up being the suction jet pump in the driver side. If I started throwing parts at it, I'd be several hundred in the hole vs. just making sure the gas doesn't get below 1/4 tanks until I fix it, lol.

[diztek]

in the morning after its been sitting all night, before you start it, check to see if you have coolant residue on the tips of your spark plugs. i had the same symptoms and my head was cracked between cylinder 2 & 3. over night jsut a little bit coolant would drown my plug. after the car got warm and idle rough for 10-15 minutes, it would be normal again, as i assume it eventually burned off the coolant. would run fine all day until it sat for a long period of time and then it would do it again.

[senecak]

PROBLEM SOLVED: Coolant Temp Sensor

Looks like I'll be returning everything else. Put the new one in. Car started normal first turn of the key. Straight to 1200 or so rpm; Slowly dropped to normal idle around 800.

As always, a big THANK YOU to everyone up here. If you can't find your answers here, you won't find them anywhere. 188,000 and we continue on....

[ErikG]

Glad to hear you got it fixed.