Hard start

EDOGS

MEMBER
2000 VOLKSWAGEN PASSAT
6 CYL
FWD
AUTOMATIC
135,000 MILES

My husband has had intermittent difficulty starting his car since this summer. It started when car was hard to start in cool damp weather. He put fuel injector additive into the tank and it would start. Right after it did start there would be one or two "pops"/backfire. Once it got going it seems to run fine. He then put 91 grade fuel in with each change and did not have the problem.

We live in dry climate, mountains of Colorado. It ran fine this fall. Now this winter when it has gotten cold and snowed, it will not start. We put in a fuel additive again, and it did start, but not until it was warmer and dryer.

There has been a very subtle exhaust or burnt oil smell in the car for a year and a half. My husband could not smell it, so it was not addressed. Do not know if this is related.

When it was run through the automatic computer diagnostic system at a small mechanic shop this summer, it showed "no problem".

1 Reply

KASEKENNY

MECHANIC
18,907 POSTS

Hard starting is normally due to a fuel issue. However, here is a guide that will help with getting us started on this:

https://www.2carpros.com/articles/engine-cranks-excessively-before-starting

I would suggest checking the fuel pressure and find out what is there to start.

https://www.2carpros.com/articles/how-to-check-fuel-system-pressure-and-regulator

Then if the pressure is correct, pull the spark plugs and find out if they are fouled. If they are then you may have too much fuel. At which point you want to do what is called a clear flood start. You do this by holding the accelerator to the floor while cranking the engine. This will cut the injectors off and if the engine starts it is due to having too much fuel.

Please see below for the chart on how to tell if a plug is fouled. Please run through this material and let us know if you have other questions. Thanks

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