peanut

944S2 1989
I'm fed up with this car by crikey .
6 weeks its sat unused and I have no other transport atm.

It really tried to start today. It coughed and fired coughed and fired but as soon as I gave it some throttle it stopped trying and just cranked over.

It must be very close or it wouldn't fire at all.

I jumpered the DME and could hear the pump, and cold start injector but not the injectors. maybe they are stuck with crud

Grandpa#3

Peanut, find a place you can send the injectors off to have them refurbished, cleaned, new seals and hat. At least you will have one less problem. Have you checked the speed and reference sensor connections?

No Start Check List, I hope this will help.

This has been extracted from a past post, authors Billysdad and John_AZ on a Start Problem.

Posts: 364
Re: 1987 starting problem
« Reply #1 on: Jul 25th, 2009, 10:28pm » Quote Modify

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Hmmmm.... that could be alto! you really have to go step by step and check the ecu harness and voltages to each area as you go. Here is a list of some test you should do one by one and eliminate problems.
Air/fuel/spark/compression
start by making sure we have a battery that is in spec.
all fluids topped off
no obvious broken wires and all vacuum hoses intact on visual inspection.
OK we have 12v at the battery with adequate cranking voltage we get in and turn the key.
12v from battery to ignition switch
12v from pin 50 on switch to pin 4 on DME plug (start signal)
12v on pins 1 (ignition pulse to ign. coil) and 18 (to G5 dme relay power supply)
12v pin 30 at DME Relay (fuel pump power supply)
12v to pin 86 at DME Relay in the run position (primary coil voltage)
12v to coil + black wire to ground 12v to - (green wire) to ground
12v to one side of the injectors
All ground contacts are clean
Fuel pump will run if DME Relay is jumpered 30/87/87b
Fuel pressure at the rail is psi +/- 3 (jumpered 36 psig)
20 minute leak down not under 14.5 psig
Fuel flow rate is 28oz after 30 seconds
Ignition coil primary resistance across + and - is between .4 and .6 ohms
Secondary resistance is between 5000 and 7200 ohms
Ignition wires are good no cracks or splits including coil wire and seated
Plugs are properly gapped
Ignition rotor is seated correctly with the set screw
Timing belt is installed correctly
Firing order is correct - 1 - 3 -4 - 2
Reference sensors are gapped correctly with .8mm clearance off the flywheel
Reference and speed sensors resistance checks in spec pins 8 and 27 speed 600-1600 ohms and pins 8 and 23 >1m ohm
Reference and speed sensors voltage checks 2.5 and 2v on oscilloscope (good luck)
Reference and speed sensor wiring is not broken at connector to sensor or to dme
OK, I'm tired anyone else want to add or be more specific?

John_AZ
Do a compression test.
Reference Sensor Tach bounce when attempting to start the engine. The Tach bounce is very slight-1/16 of an inch. Clean connections as mentioned above.
Injector "noid" light. Very basic tool but will tell you if the DME is sending a signal to the injector. An oscilloscope is the best.
Clean connections at major parts like AFM, ISV, throttle body.



Cheers,
Larry

peanut

I've checked so much so many times my head is spinning.
I've lost the will to live Larry

You are right about the injectors of course. I am lucky that there is a place locally that will clean and check them (10 miles away)

only problem I'm out of work and broke so I'm reluctant to get my injectors back with a $200 bill for clean and test and a message saying I need 4x new injectors at $250 each.

I think I'm going to have to bite the bullet and remove the fuel rail with injectors and test them in situ .Rotton job when its cold and pouring with rain and you're working outside

peanut

thank you Larry a good aide memoir. I have complied several huge check lists and I'll construct another final check list for tomorrow weather permitting. Thanks for giving me some motivation

Jfrahm

I assume this isn't an old 924 with CIS and a cold start injector. If it is, you might check the 924 boards for help.

Have you tried a puff of "Start ya Bastard?" That'll help determine if it's fuel related.

Is it turning over faster than usual? If so it might have jumped time.

Check for the tach bounce

Does it have an alarm? Immobilizer?

peanut

Not since last month when my 75 year old neighbour was passing with her dog and heard me

Sorry its a 944S2 1989 .

Tomorrow I'll check the HT system again and the tach bounce but I'm dreading removing all the console to get at the immobilser. I'd like to remove it completely one day when I've taken enough brave pills