byronjet

Turo rentals have been fun for the last two weeks but I really need to get my 99 running again.

1999 Carerra 4 Cabriolet 5spd w/ 175,000mi

Driving to work on a rainy morning the engine stopped quite suddenly. No sputtering just off like a switch.

The engine cranks over fine and I have confirmed fuel pressure ~60psi. So I believe it is a no spark scenario. Spraying starting fluid in the intake also does nothing when cranking.

Just replaced the crank position sensor with a new one and still nothing.

I have a new cam position sensor which I haven't installed yet. do they suddenly fail and cause a no start or run condition?

I'm also thinking about the immobilizer under the seat. If it is faulty will it still allow me to crank the engine?

Appreciate any tips as I continue to diagnose this guy.

Many thanks

Prelude Guy

Don't start throwing parts at it hoping something sticks.

Usually an issue with the immobilizer affects the windows, radio, and cranking. Never hurts to check it though. I always check the easy stuff first.

Is it throwing any codes?

When it cranks, it sounds completely normal? Just doesn't start?

byronjet

No problems with windows, radio or cranking.. I'll check for new codes in the AM. Before this issue I had a secondary air injection flow code.

Porschetech3

Probably not Immobilizer, it usually effects cranking.

It may sound silly but check the fuses, there is one named "engine electronics" that can blow for various reasons and cause a "no start"..

byronjet

I only have an OBD code reader and nothing is logged on the ECU, I'm sure any codes that were in there were cleared when I had the battery disconnected.

Checked all the fuses, replaced two (cigarette lighter and headlight washers)

Cranking sounds normal

byronjet

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​​I'll double check the engine electronics fuse. Thanks for the tip!

byronjet

@Porschetech3 I owe you a case of your favorite brew. Fuse C2 (Ignition, fuel injection, oxygen sensor heating) was blown. Not sure how I missed it the first time round. She is running again! Many thanks to the community here.

​​​​​​Any common causes for a blown C2 fuse? I was driving in the rain and went through a good sized puddle at speed when it blew..

Porschetech3

Coors "Silver Bullets" has been my favorite beer since the mid 70's when it was "Bootlegged" into Alabama, (hence the movie Smokey and the Bandit)..

Fuse C2 goes to a relay that powers up the 4 oxygen sensor heaters, 6 fuel injectors, 6 coils.

I would start by looking at the 02 sensor heaters, drive it a little and scan for codes.

A short anywhere in the wiring or injector, coil, 02 sensor will blow the fuse.

If you had a Durametric or PIWIS, you could see the 02 sensor heater resistance values and it could possibly speed up the diagnosis..

There is a good possibility that the water puddle contributed to the short circuit..