93 850 with 256k stalls and won't start

mbarron · Post by **mbarron** » 17 Aug 2009, 18:39

Wires are according to firing order.
12453 , clockwise viewed from driver's
side of car , with wire #1 at tallest position
(at about 10 o'clock )
There is spark(yellowish) at all plugs.
Belts are in good shape. Gas pressure rises
quickly to 43 psi in rail. With the ignition on,
I find battery voltage at BOTH wires in the connectors for
the injectors. I have swapped out CMP sensor
for one from a running 98 s70. When I shoot
starting fluid into the intake, I can not get the engine
to even cough. The engine turns over well. The timing
belt was replaced last summer. This sucker stalled at near
idle and will not start. Any advice?
Many thanks, Mark

Post by **confused_al** » 17 Aug 2009, 20:22

Any trouble codes?
http://volvospeed.com/Repair/a2.html

Post by **Ozark Lee** » 17 Aug 2009, 20:26

1-2-4-5-3 clockwise is backwards, it should be CCW. It is amazing that both Haynes and the factory manual both got it wrong.

This will work for you.

http://volvospeed.com/Repair/sparkplugs.php

...Lee

mbarron · Post by **mbarron** » 18 Aug 2009, 07:37

Ozark Lee, You are sharp and I am not, I meant counter clockwise
not clockwise.
confused_al, unfortunately I don't see any code, just 1-1-1)
There should be codes. System must be hosed.
I have yellow spark at all plugs. I got the following compression
readings (psi) for cylinders 1-4 (battery pooped out for 5)
75,85,98,65. I think I need what is called a noid light. I am going
to the autoparts store today.
Can anyone give me a list of things(other than ECU) that could cause
injectors to not fire, given that I find battery voltage at BOTH wires
in the injector connectors. I doubt for example that say a Vehicle
Speed sensor could make the injectors not fire. The resistance there is 1740ohm not the expected 200 ohms. How about water temp sensor?
Thanks, Mark

Japedo · Post by **Japedo** » 18 Aug 2009, 07:47

those compression numbers sound low to me... Im thinking that they should all be well above 100 psi. My engine has just over 300miles and is around 120ish in all cylinders.
That being said I don't think that would give u a no start condition. Are you 100% sure that your injectors arn't functioning? Did u test voltage with the engine cranking over?
One area I would check is directly above the radiator, there is that removable plastic cover that kind of clips ontop of the rad. There are a few relays there and one is the system relay. I had a damaged wire there once that was hard as hell to find. It caused me a no start condition due to no fire. But there is 4 wires going into the relay and maybe ine controls fuel. It's a longshot but just check the wires and connections in that area.

curtis

mbarron · Post by **mbarron** » 18 Aug 2009, 11:44

I just got a set of noid lights on rental. I plug in the Bosch one
and cranked, 5 revolutions twice. I seem to get an initial bright
flash in the first rev and then maybe 3 revs without a bright flash
followed then by a second flash. After one of the sets of revs I got a bright flash after I released
the starter button I used. I see some very dim flashes during the
5 revs. What should I see? I expected a bright flash once per rev.
The possibilities that occur to me at this point are:
1. Timing belt slipped. It is not broken. I doubt that a relatively new belt would decide
to slip for the first time at low revs, and low acceleration, or?
2. Some crud broke loose and almost completely plugged all
injector at once.
3. ECU is not firing injectors correctly.
Question: can I move an ECU from my 98 s70 to the 93 850?
Japedo, how do I test the voltage at the injector connectors while cranking -- what should I see? With ignition on and without cranking, I see 12.8V at both wires, testing individually. I now have
both DVM and noid light.
I would love to pull the injectors out and see them perform. I hear however that they are a bitch to get back in place, or?

Japedo · Post by **Japedo** » 18 Aug 2009, 12:29

I am not 100% what voltage you should see while testing at the injector while cranking.
Use a volt meter, just hold the ground on some grounding location under the hood and stick the positive into one of the wires at the plug connection going into the injector. I think both wires are around battery voltage with ignition on and pulsate while cranking. "I think"
Pulling the fuel rail off and inspecting the injectors is easy to do, and reinstallation isn't hard either. There is only a couple bolts. Just be carefull to not lose any of the rubber o rings and reinstall everything in the same order.
Did you look for the system relay above the rad? Sounds like a damaged wire somewhere to me.
also is your compression really that low in your cylinders? was the engine warm when u checked it?
good luck

Post by **Ozark Lee** » 18 Aug 2009, 14:25

You '93 should have the MFI LH 3.2 which has all of the injectors firing simultaneously. I'm not sure of the frequency but my guess is that it should fire every 1/5 of a revolution. Which wire are you plugging the light into? The green wires should have constant battery voltage on them any time the key is on and the grey wires pulse to ground to complete the injector firing circuit.

Your '98 likely has a Motronic ECU with is a totally different animal. You can't swap the ECUs.

...Lee

Post by **confused_al** » 18 Aug 2009, 15:36

mbarron wrote:have swapped out CMP sensor
for one from a running 98 s70.

After you swapped CPS did you try to pull codes from A6? Did you clear the codes if you had one?

This is the Trouble DTCs library:
https://www.matthewsvolvosite.com/forums ... hp?t=10758

Lee, I wonder if there is a bad CPS feed ECU would not firing injectors, is that right?

mbarron · Post by **mbarron** » 18 Aug 2009, 17:35

I pulled codes prior to swapping CMP from s70. I found no errors
only 1-1-1. I swapped in the newer CMP. At that time I did not pull
codes. I then swapped back in the original 850 CMP. I now have many 3-1-4 codes. When I first tried to get codes now, I saw what was unexpected behavior. It is as if the system was doing some sort of self check, there was a rapid ticking somewhere near the air intake, then a fan near the front and then the fan inside the ECU box. There was a lot of rapid flashing of the error code light. This sequence repeated at least one more time. Then I got codes to come out. There were eight 3-1-4 codes in a row before I quit. I did not continue until I got a 1-1-1.