1984 911 3.2 Cranking but won't start

[1stcarpaidfor]

Sorry about the double post, I was informed that I was in the wrong forum...Anyway, this car has been stored, not driven since 1999. Recently put in new Battery, fuel and started right up, but smoked like crazy from all over/around the engine. Shut it down and was talking to my wife about it and she reminded me that she drove it last (10 yrs ago) and put oil in the gas tank. I drained/cleaned tank, flushed fuel line-also used fuel stabilizer, changed filter, new plugs. Now, car cranks and seems like it wants to catch for-about 3-5 seconds, but doesn't completely turn over. Any suggestions? I usually do most (about 90%) of my own vehicle work, so I feel I am able to handle this without going to technician, I hope! Thanks for your input and patience.

[JohnJL]

D'oh! Did she really wait 10 years to admit to it?

Spark, fuel, compression.

Are you getting spark? Can you confirm with a timing light or even better with a spare plug grounded on the motor while cranking?

If you pull a plug does it smell like gas?

You might have to let the fuel pump run for a few minutes (not starting) then flush out the tank again. There might still be fuel in the lines, or even worse gunking up the injectors.

[ALXinNZ]

As already posted above fuel spark compression.

Check if your fuel pump is turning on when cranking ( put your hand on the pump ). If not change the DME relay and she will be sweet.
If it is turning on then I would check your distributor cap and rotor. then check for spark.
If that fails I would give your injectors a few small tap's with a hammer ( not hard just a gentle tap will do) as they tend to stick after a long rest.

If that fails then you need to get out the big guns and start with checking the fuel rails for oil ( from the earlier accident with the oil in fuel), if clean then check pressure. If pressure is low you can start with the fuel filter inspection. It will tell you if you have to drain and clean the tank and fuel lines.
If pressure is good then you need to start looking further at ignition, replace the plugs ( probably not needed but at least you can eliminate them from the problem) they have been sitting around for ten years, probably clogged with old oil residue......

If you still cant get it to run. best you take it to a Porsche work shop or put it back in the garage for another ten.

Best of luck

Alx

[kidrock]

I'd check the plugs, if oil had been put in the tank. Clean, gap and reinstall if necessary.

You might get it to start by using some starting fluid. Give her a quick spray in the hose connected to the ICV, reconnect the hose and have your wife turn the key.

[1stcarpaidfor]

Ok, update...Good spark, fuel pump, DME relay, fuel filter, all good. This is what air flow sensor box/chamber looks like



Gonna clean and retry.

[1stcarpaidfor]

New update:
Had a guy say might be air in injection system, (after sitting for a few minutes, car will start but not stay running more than 2 to 3 seconds), so i opened pressure check port, ran fuel pump until steady flow. Checked fuel pressure, approx 40psi, getting spark, plugs get fouled with gas, sometimes get a backfire. No steady start though. Timing appears to be good. Could fouled MAF be a/the problem? I'm at wit's end. Trying to avoid towing to nearest Porsche repair shop, 2hours away.

[kidrock]

Clearly, your entire intake system is gonna be gummed up with crap. You've already gone as far as opening up your MAF. Clean your plugs, injectors and whatever else sucks gas and air. Just for good measure, run a can or 2 of Techron or Seafoam through your system.

Just a lot of good old fashioned elbow grease is what it's going to take.

[1stcarpaidfor]

slight progress, going through a cycle of try to start, clean plugs, held maf open and got positive results, getting smoke and gassy, oily residue up in maf and air cleaner area.

[rusnak]

Are you still running the oil gas? If so, drain that out and put clean gas in the tank.

I saw a website once that showed how to test the afm with a 9 volt battery. I don't know if it's bad form to post a link to other forums.

Here's another interesting video of extending the life of the afm. However, you can get good used ones for about $100. YouTube - Rejuvenating a Bosch Motronic Air Flow Meter

[kidrock]

It's probably gonna take some time to burn all that crap out. The longer you can keep it idling, the more crap will extract itself.

[KTL]

You didn't say whether or not you drained the oil. If the oil level is over-filled, you will have an intake manifold filled with oil and that can quickly foul your plugs. The backfires can be what is contaminating the MAF because the oil overfill can be spit through the oil tank vent hose, which incidentally is connected to the rubber elbow on the throttle body. So it is being spit right back into the intake system!

I would clean up the MAF as best as possible and also remove the bottom "waffle plate" to see if the wiper contact board is contaminated with that grey goop crap you pictured.

[1stcarpaidfor]

Just finished for the day, looking promising. After each iteration of clean plugs, blow out intake and head, alternate holding maf open then closed, car acts better, actually ran (putted) for about 30 seconds. Blowout through intake is no longer black oily, just slightly wet now. Didnt think about the inside of the the maf maybe getting contaminated, but I have seen the procedures on the net as suggested by rusnak. Up early with another try. I'll keep posting.

[not sharp]

Last summer, at my golf course a grounds worker used diesel fuel in an engine that is gasoline driven. Clean all fuel system components including filters repeatedly. All will be well.

[rusnak]

I have to ask. You are not running a catalytic converter are you? Those things are expensive and not indestructible. Hopefully a cat bypass.

What do you mean blowout through the intake? Your oil level must be wickedly high. If you have a cat, it's toast by now.

[scottb]

It sounds like the car is a perfect candidate for a Sea Foam treatment.

Details here: Sea Foam | Motor Treatment

[KTL]

Also keep in mind that the engine is likely running/firing better now because the rings have become un-stuck. When an engine sits for a long period of time, the rings do not seal the cylinder walls well. Usually adding a tablespoon of oil to the cylinder (thru the spark plug hole) prior to startup helps to initially seal the pistons to the cylinder wall, when the rings are still sticky.

Glad to hear it's improving. But I think you've still got a lot of work ahead of you. Definitely some treatment is in order to clean the engine beyond the fuel injection. To clean the injection, i'd recommend removing all of the injectors and having them ultrasonically cleaned and tested. New fuel filter, possibly a pump and complete flushing of the fuel tank and lines is in order. Oil sitting in the fuel that long can promote much worse varnishing vs. old, clean gas sitting for a long time.

[rusnak]

Originally Posted by KTL

Also keep in mind that the engine is likely running/firing better now because the rings have become un-stuck. When an engine sits for a long period of time, the rings do not seal the cylinder walls well. Usually adding a tablespoon of oil to the cylinder (thru the spark plug hole) prior to startup helps to initially seal the pistons to the cylinder wall, when the rings are still sticky.

Glad to hear it's improving. But I think you've still got a lot of work ahead of you. Definitely some treatment is in order to clean the engine beyond the fuel injection. To clean the injection, i'd recommend removing all of the injectors and having them ultrasonically cleaned and tested. New fuel filter, possibly a pump and complete flushing of the fuel tank and lines is in order. Oil sitting in the fuel that long can promote much worse varnishing vs. old, clean gas sitting for a long time.

I agree. Flush out the fuel system with clean fuel. I'd even jumper the dme socket to make sure the fuel pump is working correctly. Then remove the intake system and clean the intake manifold, throttle body, afm, the ICV, and send the injectors to a cleaning service. Drain the old oil, and re-fill to the correct level. The ICV probably does not even work correctly. The air bypass screw in the AFM is probably all clogged up as well. This is way beyond Seafoam.

Otherwise, you are just running the engine and forcing it to ingest all that gunk. I would quit running it like it is.