964 only running on 123 cylinders Help

daleint · 11-25-2007, 11:02 AM

Just thought I could get some help with this 964 3.6l 1992 engine. Cant get the old girl to fire up on 4,5 and 6 cylinders. I thought I had the timing right set No1 cyl to TDC and valve timing done with drop clock (DTI) then turned 360 degrees and did the same on No4 cylinder. set the timing on distributor, turned engine over about 20 times by hand checking the DTI readings were correct and then put engine back together. fired her up and the exhausts get warm on 1,2 and 3 but stone cold on 4,5 and 6.
Petrol getting though I checked the injectors could I have messed the CAM timing up somewhere, Maybe being a first time thing setting the 964 timing up I have missed the plot.

daleint · 11-28-2007, 11:12 PM

Well I placed a thread in the 964 section but still have no answer to the problem yet. It would be good if I had all the test gear but I have not at the moment. The engine runs on 1,2, and number 3 cylinders and I have just had the rocker cover off the 4,5 and 6 intake valve and re checked the valve timing and all is ok and goes as follows. No1 at top dead center then move crank clockwise 120 degrees and checked number 6 and valves closed and all ok then another 120 degrees and number 2 ok then 120 degrees and checked number 4 and the Z1 mark is lined up with the mark on the housing. Turned the engine over about 10 times to make sure all was ok and even checked the compression was ok on N04 and all was ok. I put the rocker cover back on spark plugs in and fired the beast up. again only runs on 1,2 and no 3 cylinders. went and purchased a new DINN 88 battery and the car turns over much faster but still not running on 4,5 and 6. could anyone give me details of what to try next or procedure's to check.
Looking

MarKoBrow · 11-29-2007, 04:14 AM

It sounds like your ignition or injection might be at fault, I am not sure how the 964 operates ie: whether it is a batch fired or sequential system. I think you should first check for compression, Spark and fuel in the suspect cylinders first. You then should be able to at least point yourself in the right direction

Mark

hcoles · 11-29-2007, 05:46 AM

are you sure re. timing... the z1 mark comes up 2x per 4 cycles... this happened to me... I had one cam 180 out. however it seems that you have checked and rechecked this

you want to be on the part of the cam... that has both int. and exh. closed for a "long" time before and somewhat "long" time after tdc and at tdc the rotor is pointing to the wire for that cylinder... if you are on the overlap you are 180 out.

2.7RACER · 11-29-2007, 03:26 PM

Kiwi,
The injectors 4,5 & 6 share a common wire, red/white. 1,2 & 3 also share a common wire red/white. The remaining signal wires from the DME are individual for each injector.
My guess is the cam timing is OK, you seem to have checked it correctly, then the issue is power to the injectors.
What isn't clear from reading the schematic is whether the shared red/white wire is ground or 12 volts. Really don't care at this point.
You need to locate the red/white wire for the 4,5,6 side and check for continuity with the red/white wire from the 1,2,3 side.
Do this with power off. They all go to a common point and are connected.
The connectors to the injectors are two wires. One is the red/white common to all 6 injectors.
The other wire is individual to each injector back to the DME.
If you can listen to the injectors while running likely the 4,5,6 side is not buzzing.
Good luck,

john walker's workshop · 11-29-2007, 06:21 PM

pull the upper covers and check the intake valve for clearance in proper firing order. set to Z1 for #1 TDC, wiggle the rocker to feel the clearance, 1/3 turn to #6, should have clearance, and continue through the firing order. checking to see if one cam is 180° out. i assume you were setting the cam timing, although you didn't really say it.

DW SD · 11-30-2007, 12:55 PM

As I had suggested in your 964 thread - can you purchase a diagnostic light that you can plug into the injectors on the dead side? It is simply a test light with proper interface and resistance to plug into an injector connector. I think you can buy one of these at any autoparts store for minimal $. Here they might cost $10.

Might help with your troubleshooting of electrical vs. mechanical.

Doug

daleint · 12-06-2007, 12:02 PM

I purchased one of those LED testers for the injecters and it seems to pulse ok. I have decided to take the bottom rocker covers off and exhaust and check the CAM thing again and if that does not work Ill take the engine out again. Thanks for the info and any other ideas you may have regarding the problem would be greatly recieved. Cheers
David

Eagledriver · 12-06-2007, 01:10 PM

I'm not familiar with how the spark plug wires are routed on the 3.6 but since it's twin plug is it possible you have the plug wires mixed up so the spark for the dead bank is 180 degrees off? (i.e. bottom plug wires for the right bank is really on the left bank, etc.)

-Andy

hcoles · 12-06-2007, 04:29 PM

when my cam was out 180.. I smelled unburnt gas when I pulled the plugs - are the plugs wet with gas or smell like gas? this may help confirm if the injectors are opening or not

daleint · 12-08-2007, 05:00 PM

Just been over the car again and next step is engine out. this is what I have.
TDC and compression and firing position on number 1 cylinder. I re checked the valve timing and when rotated 360 degrees I have 1.1mm movement on DTI set on inlet valve on number 1.

Turned engine to TDC on number 1 (firing stroke) and turned the engine over 360 degrees number 4 is on TDC and "Z1" mark is all ligned up. I then set DTI to zero and re checked the valve timing at 1.2mm at "Z1" mark when engine was rotated 360 degrees. Gap was set at .1mm for rocker and I can only think having the engine running had bedded the new parts in thats why the valves have rockers have moved from 1.35 mm as they were set in the first place.

daleint · 12-08-2007, 05:12 PM

The alternator light also came on as if it was not charging so thats going back to the auto electrician to re fix and we will re set the engine up. and re check CAM's timing etc. would the differance in measurement on the valve 1.1mm to 1.35mm cause the engine not to fire on 4,5 and 6 cylinders?
The CAM on the left bank (1,2 and 3) has lobes almost directly opposing each other where the CAM on the right bank has a profile where the lobes are almost next to each other. both CAM's rotate anti clockwise and the crank clockwise.

daleint · 12-08-2007, 05:14 PM

Plugs were not wet when we removed them. All leads are numbered so we got those in the right place.

john walker's workshop · 12-08-2007, 06:02 PM

you would barely notice that minor difference. gotta be something else.