Not starting '95 what to check next.

[jcasteel]

For those that care, this is the D-90 that the rats got into.

I think I've read all of the posts concerning D-90s not starting. Unfortunately many of the threads end before the solution is presented. My symptoms are: Engine turns over fine but does not start. Humming from the fuel pump prior to cranking. On occasion the Rover does start and runs great but then the next time I try to start it it will only turn over and not start .

Being as an engine needs three things to start (air, fuel, spark) I think I can rule out air. I also think that I can rule out fuel since I took the fuel line off and during cranking I had a lot of pressure. (Of course I don't really know how much pressure and the injectors could be the problem but for now let's rule out fuel).

So, I'm looking at spark. I held the lead from the coil near a ground and turned the ignition on. I have a steady series of sparks.

Next I replaced the lead from the coil and held the wire for plug #1 next to the ground. As I turn the ignition to start I have 1 (one) spark. During cranking there are no sparks. Then many times after I release the ignition key (from start position to run position) I get some sparks as the engine quits turning.

Does this mean anything to anybody?

Other notable conditions.

1. Inside the distributor cap, at each contact position there is some blackening on the leading edge of the contact . Perhaps the spark is trying to fire too soon?

2. I've replaced the plug wire to #1 sparkplug because I pulled the wire out of the distributor end on the old cable. It is possible that I need to replace all wires but old wires wouldn't explain #1 not firing during cranking, or would it?

3. Fuel pump is brand new.

4. Fuel pump relays are new.

5. Coil is new but the old coil acts just the same.

7. The stepper motor has been cleaned and appears to function properly.

8. Perhaps the distributor cap and rotor are bad. Are there any kinds of test for these parts?

9. Last summer a rat or rats got into the Rover. I had a nest between the steering wheel and the firewall and another nest in the valley of the engine. I checked all wiring and repaired where there was chewing. I believe that I did a thorough job.

In the process I replaced the fuel pump and the fuel pump relay.

10. A couple of times after removing the hose from the plenum to the evaporative canister the Rover cranked. Also, once while the air intake was disconnected from the plenum the Rover started. In both cases I reconnected the parts while running and the Rover runs fine. However, after shutting down it wouldn't start again. Duplicating these actions does not result in the Rover running. I think they were just coincidences but I can't deny that both actions have to do with air getting into or out of the plenum.

Can anyone tell me what else to consider? I'm trying to avoid just replacing parts. But my next thought is for the distributor cap and rotor. Then perhaps the Ign. Control Module. My ICM is not on the distributor. I've found a link where the ICM was replaced with a Ford module.

I've never had a problem this hard to find!!!

Thanks for any help offered.

John

[tmore]

No help to you at this point but I have the EXACT same problem/symptoms, coil sparks to ground with ign in the start position but plug only sparks once while cranking over extended period. ( still don't understand why it would spark prior to cranking, I thought the distributor triggered this)... I replaced the cap/rotor/coil/wires and it is still dead.. I have a new ign module on order that I should see this thurs.. i will let you know if it helps or not.. If you get a chance can you let me know which wires go to which terminals on your vehicle, in past posts there seems to be some comflicting info..

[jcasteel]

I'll tell you right now...

...

+ side
thick white wire with hard connector cover
thin black wire with hard connector cover (goes to silver cylinder attached to the coil mounting bracket.
thing white wire with hard connector cover


- side
thin white wire with flexible black cover
thin white wire with flexible clear cover


The common denominator seems to be that the flexible covers go to the neg side. hard covers go to the pos. side.

This is the way it came from the factory unless...

1. The rats moved the wires.

2. My redneck neighbor came into my garage and changed the wires. However, he is cool and if he did this he would've fessed up by now and we both would have had a good laugh and a good beer to commemorate the occasion.

[JimC]

The fuel air spark analysis is correct, but there are a few other things that might have gone wrong.
- Even though there is fuel pressure, the injectors might not be firing
- The computer might not be getting good signals from the AFM or some other engine sensor, so the operating parameters necessary to run are missing.
- If the engine is flooding, the cold start valve (I think the 3.9 has one - dont quote me) might be over-enriching the mixture on start-up causing a flooding condition.
- Damn rats might have eaten the ignition resistor screwed to the firewall behind the wiper motor.

I dont know man, Is the "Change Engine Light" illuminated? :grin

[Mike Hippert]

John and Tom, I have the procedue to check the distributer at home and can post the list of things to check later on, but I would check/replace the wires running between the coil and the distributer ther should be 2 and there should also be to going to the coil 1 from the battery or +12 volts and one going from the - on the coil to the ECU and make sure they are all good.

[tmore]

Thanks John
One more quick question.. On my vehicle both of the thin white wires coming from the ignition module have hard connectors.. One wire is all white the other is white with a blk stripe.. Any chance you know which goes to whick terminal of the coil??

Thanks Tom

[Mike Hippert]

The white and black goe's to the negative the other goes to the positive.

[jcasteel]

Tom, JimC and Mike, thank you. Tom, I'll look again when I get home at the wires. I know that Mike will be correct but since I'll check my wires anyway then I'll look at the colors. Mike, thanks for getting the test documentation together for us.

JimC,

The injectors were suspect on my list too especially since the Rat family was camping out in that area. Since I apparently don't have spark I'll keep looking there for now but is there a home test for the injectors? I have a Fluke autometer but don't know what the test would be.

Is there a home test for the AFM? I'm not seeing any codes while cranking.

Cold start Valve, Ignition resistor ? I'll have to look for those. Any further clues as to their identity / location? if the ignition resistor is located on the firwall I'll have to look at that. That's the location where most of the damage occured.

Thanks all, I have some stuff to look at when I get home.

Oh, and Tom I saw your post outlining your issues. When we get these resolved I'll put together a diagnosis synopsis (diagsynop ?). Maybe you'd review it for me.

[JimC]

Sadly, I have dont know how to test an AFM or really anything else with a multimeter. I'd be going straight to the Bosch engine management books available from Bentley Publishers.

The resistor looks like a miniature audio amplifier. and is screwed to the firewall behind the wiper motor. Its good and concealed by the warning module and a couple other misc pieces of junk.

Good luck, I'm definitely not an engine management tech, so please take my input and file under "armchair quarterback" if it proves to be crap :)

[jcasteel]

For tmore,

This is color coding of the wires to my coil.

On the positive side:

Thick white wire. (This wire goes into a black flex pipe and leads to the front of the engine.)

black wire. (This wire goes to a small silver cylinder next to the coil, perhaps a capacitor?)

thin white wire. (This wire goes to the ICM, ignition control module.)

========================

On the negative side:

thin white wire with a black stripe. (This wire goes to the ICM, ignition control module.)

thin white wire with black circles. (This wire goes fits loosely into a thick black insulator. The wire and tube lead to the rear of the engine and appear to cross the left valve blank.)

If anybody can tell me what the wires do and where they actually go then I'll add that information to this post for the next person.

Hope this helps.

[Mike Hippert]

Sorry for the delay, my 90 has been keeping me a bit busy.

WARNING! You may get shocked doing some of these tests! When holding the HT wire use insulated pliers to avoid getting shocked.

OK right from the manual

1. pull the coil wire off the distributor, hold it over the engine block about 1/2" away, try starting engine spark should occur, if it does skip to step 6, if not go to step 2

2. a Check to see battery is above 11.5 volts
b measure voltage from ground to - on coil it should be 1 volt max
c measure from + on coil to ground, again 1 volt max
d measure from ground to the screw holding the amplifier on the distributor, should be 0 to .1
Volts

If all are OK go to step 3, if a is low charge your battery, if 2 and 3 are low check your ignition switch
And wiring, if 4 is high check the grounding to the amplifier

3. Measure from the coil - to the battery + with ignition off, should be 0. Switch ignition on and
crank engine, volt meter should indicate just above 0, if so go to step 5, if not step 4

4. Pull amplifier off of the distributor, 2 screws hold it on, measure resistance at connector, it should
be between 2 and 5 kohm. If reading OK change amplifier, if not ok change pickup in
distributor, also check wiring between amplifier and coil.

5. replace HT coil wire with a new one and recheck step 1

6. remove distributor cover (cap), disconnect HT lead from cap, hold the HT wire 1/4" above the rotor arm
and crank engine. There should be no spark! If good then go to step 7, if not replace the rotor arm.

7. check cap for cracks, check coil for cracks check all HT cables for cracks and make sure they conduct
(the should measure 0 ohms or there about from end to end), check/replace spark plugs.

Well there ya go, hope it helps!

[jcasteel]

Thanks Mike, I'll try these tonight if it dries out around here. I don't fancy getting hit with 30,000 volts while standing in a puddle of water.

John

[Mike Hippert]

It's not the puddle of water that will get you on an ignition system. The 30kV is looking to get back to ground on your 90, so if you are leaning up against a body panel or something grounded it will try and go through you! But it isn't that bad, I shocked myself going through these tests this weekend :)

[tmore]

Installed the a new ignition module today and it started and ran great...

Mike, John, Jim thanks for all of the help, I appreciate it..

Tom

[tmore]

spoke too soon.. It started and ran fine for about ten trips around the block then I went to run an errand and it stalled again... Differant symptons now.. It seems to start and idle well but when you attempt to give it gas and reve the engine sometime it works and sometimes it sputters and stalls..
Any suggestions??

[Davis]

I would check your stepper motor.

[jcasteel]

Tom, did you finally get it working correccly?

[tmore]

After replacing the ignition module and cleaning the stepper motor it started up and seems to be running fine.. I hope to put some miles on it this weekend to make sure..

Thanks
Tom