924Board.org

[lonestarrpm]

Pulled the engine, put her back in. All emissions have been removed.

New fuel pump. new battery.

Fuels seems fine, 3 of 4 injectors are firing. (lift and look method)

Good Sparc on all plugs.

Checked timing (3 mechanics are working on this) carefully -- more than 3 times All looks good.

We have a non-running 83 944 to compare to -- (a future LeMons.....)

We get tach bounce, both reference and speed sensors ohm out ok,
and there is voltage on both via meter (no o-scope available)

She'll crank and crank, but no fire. Good sounding pops from compression. Tough to hand crank at the right points (which we checked for timing).

Seems like we get some push back through the intake -- but hard to tell.

occasional back fire, like once every few attempts to crank. (i.e only once per set, but not every set of crank attempts).

even starter spray does nothing.

Seemed to us to be advanced timing, but that was before we knew tach was bouncing.

Somewhat stumped at the moment -- 3 weeks until race day

thanks,

Mike
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Porsche M96 Engine Rebuilds

[John_AZ]

Really hard to know what to suggest with 3 mechanics and experienced owners.

Only clue is 3 of 4 injectors are firing.

Did you make the Clarks 3 wire DME jumper? ------Maybe you have a couple of bad old DMEs

Wiggle the DME computer connector while you are trying to start. Could be a bad pin.

Check all the harness connections on top of the engine. Especially the AFM. Look at the pins in the connectors.

Fuel rail pressure??

A 4th opinion....
http://benms.com/944nostart.html

GL
John
_________________
'88 924S 67K
'87 924S 122K -DD
Past: 1970 914 1.7, 1977.5 924, 1979 924, +++== Gone, Past tutors

[lonestarrpm]

The plan tomorrow night
is to open up the DME's and see if there are any obvious issues.

We'll run compression tests tomorrow (we didn't have the gear
in the shop). The car is at a different shop than ours getting the roll cage done -- we'd hoped to hand them a runner, so now we get to work around them. Yes, we pull the DME every time the start welding

We've swapped DMEs, MAS, intakes, speed/reference sensors with similar results.

replaced fuel pump, runs with DME relay. new fuel filter
We've got fuel pressure -- just not sure how high. We'll have to bring that equipment out there too.

Will go through Clarks Sensors debug page.

probably pull a fuel injector from the 944.

One of our mechanics even races 944 Turbos -- but they are a slightly different animal. He's really puzzled

Tough when you start off with two non-runners.

I enjoy a good puzzle -- just not under time constraints

A little frustrating, but sure appreciate the help and pointers.

ready for some lemonaide

Mike
_________________
Porsche M96 Engine Rebuilds

[ic932]

The stuff from the 83 944 (ecu, afm) will not help you find the problem. Make sure you troubleshoot using the 88' parts only.

[lonestarrpm]

Can you get the crankshaft 180 degrees out of phase with camshaft and not cause damage?

One of the guys has been running a aluminum flywheel and didn't realize the stock flywheel maybe marked differently.

While researching possible issues -- I came across clarks-garage pix
which show two marks on the flywheel, one of which is 180 degrees from TDC.

We might have used that one.

It was hand cranked many times before we hooked up the starter.

Wondering if it you can run it 180 degrees out of phase without causing some sort of valve damage.

Even now you can hand crank it -- but hard to know if we already bent something and just didn't realize it.

Guess we'll find out tonite -- but was hoping to be prepared ahead of time.

thx,

Mike
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Porsche M96 Engine Rebuilds

[Paul]

Check the rotor set screw.
_________________
White 87 924S "Ghost"
Silver 98 986 3.6l 320 HP "Frank N Stein"
White 01 986 "Christine"
Polar Silver 02 996TT. "Turbo"
Owned and repaired 924s since 1977
Porsche: It's not driving, it's therapy.

[lonestarrpm]

[joecitizennn]

[lonestarrpm]

She fired right up
Even idles.

Used one of the injectors from the 944

Suspect a lose wire tho and might swap back

Thanks for the help

9 days tol we hit the track
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Porsche M96 Engine Rebuilds

[ic932]