02 jetta died while driving won't restart

The other day the jetta wouldn't start,had to have it towed home. Next day it starts and runs fine. 2 days later same thing, cranks good but no start. Checked with vagcom, has code po128, coolant thermostat valve out of range, below control range. If I view the temp it is 50 degree celsius,car is still warm. This time the car died while idling at a light. Charge system good, 13.8 vdc. Thanks for your help

After scanning the computer, went to crank the car to see if I had rpm signal and it started right up? I can't have an unreliable car, what do I check?

Also, I shut the car off after idling 20 minutes in driveway. When restarting it acts like it kicks back the flywheel, almost like a gas engine with too much timing advance

Anyone?

The temp sensors are known to go bad. there was an update from the original black ones to a green one. Its a cheap part, relatively easy to change. It would be a good start.

Check the timing with vcds. Worth the couple minutes of effort

I think a good thing to answer for us is.. how does it run when it does start, is it rough, not right, powerless, can you go drive it ok? etc

When it is in a no start condition, does the glow plug light come on when you turn the key to the on position?

Unsure of glow plug lite, it is my 18 yr old sons first car. Once running, it drives good. I can also say while it was in the driveway and I started it several times, took longer (more cranking ) then Normal to start

Also, I did the timing belt tensioner and pulleys at 85k miles. Car has 130k on it now

Crankshaft position sensor... Guaranteed...

Well, not guaranteed, but yeah, guaranteed. Had this happen to my wife over the winter... Intermittent ability to start, improved by me wiggling the sensor connector wires (noticed a few nicks in the lines on the non-sensor side of the connector)... that worked for a couple of weeks, taping the wires apart separately, then it gave up again and had the shop just replace the sensor... No problems since...

When you have the crank but no start, keep your eyes on the tach... I was getting no, or very random rpm readings....

This assumes you've already sorted out fuel issues to the engine.

wouldn't i have had a code for crankshaft position sensor if it was bad or intermittent? the only thing i see in the computer is a temp sensor fault

Anyone?

Since it is intermittent, I'd go with CPS as well.

I ordered the coolant temp sensor and crankshaft position sensor from napa, should have them tomorrow.

Hi, Just wondering of any updates....same issue here.

Did you replace one sensor at a time to actually see which one was bad?

Thanks

I wouldnt bother installing that coolant temp sensor from napa. It will give you problems at some point. Go OEM.

CTS aint your problem tho

IQ is way off after sitting 1.81, 1.88, -1.86, -1.88

I agree with you on OEM sensors...

2001 ALH, 5-speed, 244K

The problem is first start up of the day it runs like crap...shaking like running on 2-cylinders. VCDS readings cold are 1.81, 1.88, -1.86, -1.88.
She puffs alot of smoke.

Thought the initial problem was the 205 nozzles that might have been plugged, so installed a set of 357 nozzles that I ultra-sonic cleaned prior to install. Same issue with lots of smoke and rough idle.

After I let it idle for 5-7 minutes, it smooths out and the VCDS readings are .19, 1.88, -1.36, -.73

When reading the posts here, I decided to swap the crank sensor from my wifes 2002 TDI. No change.

Other info: It can sit for about 1/2 hr after running for 5-10 miles, and after restarting it's running rough for a minute or two....slightly reving the engine it clears back up and runs smooth.

When the engine is warning up, i see on VCDS that the temp is climing to normal temp. Is there another temp (or coolant) sensor that could cause this issue?

Footnote: When the car is running smooth, she runs like a scalded dog....fast and furious.

Another thing I may mention is when it's running smooth at idle, VCDS shows 2.2-2.6 mg/str , .30 liter/hr

One other thing I tested was looking for an air/vacuum leak on the return fuel line just prior to the 'T' at filter. Had to pump the miti-vac to 27/in. prior to fuel would start flowing.....minimal bubbles.

Any feedback would be great......Thanks in advance....