dgz924s

87 924S.....Car will no longer start. Thought the battery was bad but it is good. Starter turns motor over and getting fuel as I can tell it is flooded from not firing. DME relay is new. I am getting air/spark and fuel just won't fire.

I need to get this thing running before I end up in prison!

Car ran fine till one day it would not start, next day it would start and the next day no start. Makes NO sense!!!
I pulled the relay to prevent flooding and used starting fluid still no fire. I know it is going to have to dry out some fuel before I can try again but I am at WITS END and about to junk the car!!

Please help me get this BS figured out so I can make a dozen serious appointments that this car has kept me from making.errrrrrr


TIA!

M758

If you are getting spark then it is a issue of spark timing.

Speed and reference sensors can fail.

So you have fuel and you have spark, but not at the right times. So what must be happening is that the DME is telling the injectors to fire and the there is a spark. It is just not firing at the right time.

When you used starting fluid did feel like it was firing at all?

951Porschiste

I'll second that

dgz924s

No on the starting fluid. Thanks. Sounds like one cylinder wants to fire though.

dgz924s

What contorsions does it take to replace or fix the sensors?

M758

They are not that bad. They are located at the top of the bell housing. I access them from the drivers side and then reach to the center back near the firewall. There are two black square connectors that are attached to the back of the intake manifold. Follow those down.

The wires may also still be labled DG and BG.

dgz924s

Joe.......Sensors go bad over night? Do they fail totally or work half the time? I do not disagree on the sensor issue but all was ok before, just decided it would only start on it's own terms?

Which sensor is the one that controls engine start up? One is for speed and the other is TDC?

Much appreciated guys thanks!!

M758

anything eletronic can just up and fail. There is away to test the sensors. I just don't know how to do it.

The reason I am point there is you have fuel and you say you have spark. So if it is not starting then you are probably mistimed. It is unlike that the belts slipped so the mechanical timing is rigth. That leave the eletronics. The job of the speed and reference sensors is to tell teh DME the engine speed and when it hits TDC. Then the computers knows when to inject the fuel.

Zero10

I've never heard of the speed and reference sensors sending signals out of time, but that doesn't mean it's impossible.
You say you have spark, how did you verify it? Do you know for certain that you have spark on all 4 cylinders?

I wonder if maybe the set screw on the rotor backed out.

dgz924s

Spark at the coil wire. No spark that could see on #1 plug/cyl. Rotor is new as is the cap. Rotor intact.

M758

Well then... that would be a problem. Time to chase down the coil to the plugs.

dgz924s

I don't follow Joe!? If I get a spark off the coil wire using a plug to test how can the 4 cylinder wires not fire?

lleroyb

How about pulling all four plugs, reconnect the wires, tape the plug bodies to the cam tower for ground and crank it over. Check that all four get a bright blue spark. If so, that pretty well leaves timing like Joe P. said. You could look down the plug holes and see the rotor is pointing to the plug that is close to tdc, the timing would either be correct or 180 out. I also like the loose rotor idea.

Don't crank too long, remember fuel should be squirting into the cylinders which are now open to atmosphere and your, hopefully, sparking plugs.

Lou

M758

Dal,
If you are not getting a spart to the plugs, but are getting spark at the coil... .Well that is your problem. Something in the rotor probably is not transfering the spark to the plug wires.

dgz924s

Coil spark was visable but not real bright? I may not be able to see the plug spark also. Rotor is ok new in fact. Perhaps the spark is too weak to get a fire?

Boy there has to be a conspiracy! I never fumble on mechanical repairs/diagnostics, always figure it out and fix it but every last car I have owned that breaks down is an ELECTRICAL issue and I do not know a volt from static electricity. All I know is don't touch electricity! Sounds odd but so so true, every time my car is down it is some stupid electrical thing I will never be able to fix. Never have and with my lack of luck never will. I may as well have some one tow this poor excuse of a car to the bone yard or re wire the entire car with electrical components that work.

Sorry for the rant but I am so far behind in my Doctor appointments I am going to lose my benefits if I don't make these Gov't mandated appointments. So I am livid because this 924S is going to cost me my livelyhood if it does not start 4 weeks ago! errrrr