HELP FAST! Porschey might be dead!

[Rock]

Ok the Porschey is down in a parking lot right now. I was driving it, and tried to shift into 4th and it didnt go in all the way. I pushed the gas and floored it cuz i was trying to pick up speed. The rev needled bounced past 7,000 and went so far that it went into the black (it just bounced there for a second). Well the car shut off, and i was just coasting down the road. My 2 friends get out and push it, we were able to get it started again and it ran fine. We drove about 2 miles and parked it for like 30 mins, then it started right back up fine and we drove another 4 miles with no problem. Then the car died again, they pushed it and it started again. So i parked it in a pep boys parking lot, and they wouldnt even come out to look at it because "ITS A PORSCHE! I WOULDNT TOUCH THAT IN THE SHOP WITH A 10 FOOT POLE". Now i cant get the car started again. The engine was running just perfect, so i dont think the engine is damaged. Its running like it wasnt getting fuel, and yes i do have gas in it. I checked all the fuses they were fine, did i burn the fuel pump up or something?

[strath44]

Fault with the rev-limiter maybe, it cuts the engine out temporarily if its not see action in a while/ever then might have upset things. Try again in the morning also do the wiggle test on all the relevant wires. It does sound like something might have burnt out/blown. Hard to tell without trying stuff individually and checking relays etc. How are the electrics? What happens when you turn the key?

[Tishabet]

When you say the needle bounced past 7000, do you mean that the engine went past 7000 or do you think the tach alone bounced? Just trying to clarify.

[TCMdocs944]

Basics first...Check all fuses....Make sure all relays are secure...Make sure battery and grounds are clean.....

This one is new to me but I am thinking DME, Relay or something of the sort.

Maybe the rev limiter needs to be "reset" (just a wild thought). Disconnect battery for a few minutes and reconnect.


Whatever you did you definately pissed her off.

[AFJuvat]

Disconnect the battery, let it sit for a few.

While you are waiting....

Spin the motor to TDC - make sure the cam and crank line up.

IF they do, reconnect the battery and try to start again.

Still no start:

do a compression test.

You may have floated your valves

AFJuvat

[Rock]

FLOATED MY VALVES? UH OH SPAGHETTI O's.

The engine didnt run ANY worse, wouldnt floating valves make the engine run crappy. When i redline 2nd, i reach 60 mph, i redlined 2nd with 2 other people in the car and still reached 60. Sound like floating valves? The car cranks fine, it just wont fire up. I checked all the fuses, secured all the relays. Could it be that i somehow broke something that delivers fuel. It doesnt sound like its getting fuel.

Thanks for the tips so far guys, i miss this car, i wanted to cry when i had to drive away from it and left it sitting in a pep boys parking lot.

[Rock]

i think the tach alone went, i left my foot off the gas pretty fast. it wasnt even up in the 7000 range but for less than a second

[Tishabet]

If you think the tach indicated 7000 but the engine wasn't at 7000, I would check your speed and reference sensors. I'm not positive, but I believe that the sensors are where the signal for the tach comes from, and if those sensors get screwed up you'll definitely be having problems.

[fast924S]

Swap out the DME relay, also see if you can hear the Fuel pump runnign when you are starting the car, One time when I was beating on my 924S the pump died and I couldnt get her started

[Rock]

when i have the key in the position where just the electrical stuff runs, i can hear a small winding sound, is this the fuel pump? How can i tell if the fuel pump is gone? And can i switch the DME relay with another different relay? I dont have a spare DME relay.

Thanks so much for your help guys! I wanna get this car back on the road, i love it a lot.

[Zero10]

Nope that shouldn't be the fuel pump. It is activated at one of two times, 1) starter motor is powered, 2) engine rpm is above 300rpm.
Could try jumpering the fuel pump if you think it failed.

A quick way to check the sensors is, look at the tach when it is turning over. If the needle is moving, then the DME is getting the signals from the speed/reference sensors.

Could check it out with a stethescope to see if the injectors are firing (don't know why they wouldn't).
Check if you have spark. Lay a spark plug on the the valve cover and turn it over. Have somebody check for spark. Don't do this for long, because it will expel gas mixed with air through the spark plug hole if all is well, and it should quickly reach the spark plug. Come to think of it, pull the fuse for the fuel pump and turn it over for a bit prior to the spark test.
That is, unless you have another way to test (i.e. proper tools).

There's a couple guesses.

The engine should never be able to hit 7000RPM, rev limiter is 6200. So 99% sure it was just the tach needle bouncing up. Plus many of our gauges are inaccurate at near full scale deflection. (i.e. speedo!!)

If you floated a valve, it definately would not run well, and it should still catch if only one is damaged, maybe if 2 or 3 are damaged. But it should be backfiring or something if that is the case.

I agree you pissed the car off. For some reason porsche's have emotions... you don't want to get one mad!

I second turning it over checking for the alignment marks for TDC, but it would turn over really fast if there were bent valves (usually).

[serge944]

You can also be old school and spray carb cleaner down your intake. If the car tries to start, then youre probably having fuel delivery problems...most likely the fuel pump.

[TCMdocs944]

I need a clarification though...

Are you saying your car - will not start - now?
Only hear starter spinning?

[Rock]

right the car will WONT start but it does crank over....??

[TCMdocs944]

Do as Obi wan Juvat says...

While ckecking TDC (it is very easy if you haven't done it) make sure that the belt is in there too.

[Turn the crankbolt clockwise. It should turn without too much effort, even easier if you remove a spark plug.]

[Rock]

Well seeing as how i dont know what the TDC is, can you explain to me how to check that?

[Tishabet]

Go to clarks-garage.com and look at the garage manual, under finding TDC aka "top dead center." It's the top of the piston travel on cylinder one.
So...uh....never changed your belts huh? Any kittens dying under the hood?

[Z-man]

Rock: How did you miss the shift? I think the culprit is you trying to slam into the next gears while accelerating. BTW: That does NOT save any time in your shifting, and can cause premature wear on your shifter/tranny. When shifting, take the shifter out of gear using the pressure of 2-3 fingers only, move it across the neutral plain, and then into the next gear. Break the shifting into 3 separate sections, be gentle with it, and you will see that you don't loose any time shifting this way vs. the 'slam if you can find it shifting.'

BTW: I drive my car on the track, and regularly bounce of the rev-limiter. It is there to protect the engine, not to damage it!

That said, I think you're hitting the rev limiter is just a coincidence to your car's present condition. Sounds like you drive your car pretty hard. (redline in 2nd at 60mph...etc). Driving these cars hard can lead to such issues.

You can check the pressure on the fuel rail as well: take the cap off the end of the rail, and check the bolt for tightness. You can loosen the bolt, but be careful! If you have pressure, gas should squirt out. (Don't loosen this bolt all the way! ) Tighten and try to start the car again.

Another thing you can do is when starting the car, depress the throttle all the way. Don't pump it: just press it all the way down, and then try starting the car.

I suspect that if the fuel pump is working, there may be something blocking the lines.

Other things to check: oil dipstick and coolant overflow container: if you see a milky substance in either, then you may have a blown headgasket.

IF you still can't get the car started, you may want to take it to a Porsche mechanic and have them check it.

Good luck!
-Z.

[rammstein]

Its been mentioned, but not in full detail. If you want to rule out once and for all the fuel pump, open your fusebox and find the DME relay. Pull it out. There will be slots underneath it, and these are labeled. You want to take a piece of wire (I used a 15 gauge speaker wire with some spades crimped onto the ends) and push it into terminals (slots) 30 and 87b. If you hear a loud noise when you do this, your fuel pump is fine. If you hear nothing, you have a problem. For pics, see my old post on fuel leaks where I performed the procedure listed above.

Link: How a fool managedto fix a fuel leak

I don't know what is wrong with your car, I hope you figure it out soon. I just figured I'd mention this part cause I had done it once.

[MrPants]

Yea DME relay is definately the first thing to check