93' 245 Cranks but No Start

So recently I picked up a 93 245 that cranks but won't start. The guy who had it last said it was running, then started to stumble and fail. He replaced the AMM with what looks like a JY unit. He was a Ford car guy who didn't know anything about Volvo's. The only other information I got from him was that he had plugged and unplugged the AMM while the car was running, but I don't know if that causes any failures.

Since then I have.
-Changed the ECT Sensor
-Replaced the Spark Plugs
-Replaced the CPS
-Replaced all fuses in fusebox and brushed down the holders.
-Verified the cam dowel still exists and the cam turns during crank
-Verified spark both physically and with a timing light.
-Checked for codes - 1-1-1 from ICU and ECU
-Checked the CPS, injectors, and IAV with the obd unit.
-Checked the injectors with a noid light, they flash
-Checked fuel pressure at the rail
-Checked for fuel from the fpr
-Cleaned the grounds at the rail.
-Checked compression
-Tried to start the car with starting fluid.
-Checked for blockage in the airbox.

The car cranks over beautifully, but doesn't start. Sometimes when you turn the key off, it will stumble and diesel along for a second or two. Seems to do this more when using starting fluid. Checking the new plugs, they show no carbon/signs of ignition at all, and seem to have quite a bit of fuel on them. The oil also smells like fuel. It behaves the same with the AMM plugged in or unplugged. It also has a relay by the battery (I believe the AC relay) that appears to have melted partially at some point.

I'm wondering where to go next. I know I need to physically verify timing. I should double check the new ECT resistance. I don't know what would be causing the flooding though, seeing as spark appears to be present.

Would a failing powerstage cause this? Spark plug wires possibly not clicking onto the plug heads? A failed ICU or ECU that still throws 1-1-1 codes but is dumping fuel or erratic timing? Can a bad AMM cause a no-start condition? Would a stuck injector still tick during the OBD diagnostic? Would a flywheel installed by a previous owner in the incorrect position cause this?

I have a 2.4 turbo ECU and EZK box on hand for the future, but I've been hesitant to throw them in the car to troubleshoot. I'd appreciate any suggestions with where to go next.

A failing power stage could cause this problem, for sure. You can try taking it off and reapplying thermal paste. It might be dead, but mine bounced back a few times after some cleanup. Spark plug wires would be more likely to cause stumbling. I think I read on the FAQ that a failed ECU can put out way too much fuel. Might be worth it to look for and replacing obviously burned components on the board. If it isn't a ROM or ASIC that failed, you might have a chance. My AMM prevented starting when it failed. But the AMM is probably not the problem if the car still fails to start after unplugging it. Not sure about the other things. Never had a car fail to start because of injectors, and I haven't had to work on the rear side of an engine yet.
One time my car failed to start until I pressed down on the diagnostic unit's lid. It was stuck in a crank/no start 2 days and I had already thrown the parts cannon at the ignition system. Then I press down on the diagnostic unit A lid, go to start the car and it fires right up.

Check that the timing belt hasn't slipped.

Easier still, check that the distributor isn't installed 180deg off -- crank over by hand until timing pointer is at TDC, check that #1 cam lobes (through oil filler cap) are pointing up left/right, then check that the rotor tip is roughly over the notch/scribe line in the edge of the disti housing. You can also use a dowel through the spark plug hole to confirm TDC. Firing order is 1-3-4-2 and plug wires should match as the rotor turns CW.

check OBD codes

It is time to diagnose your problem with the car instead of guessing and throwing parts at it. Have you verified there is spark?
The first thing to check is that the fuel pump relay is turning on the system side of the relay. If that is working. Then check for spark. Use a test light to verify that the relay is turning on the system side of the relay.
If you have no spark and the system side of the relay is turning on. then it's time to check at the coil for switching signal wiht the test light. On terminal 1. No switching? Move back to the ignition amp on the inner left fender. Use a meter to see if the switching signal is coming from the EZK box. If it is then try another ignition amp and veryfiy wiring connections are clean and tight. If there isn't verify wiring and try another ezk box if the crank position sensor is known good. If not known good then try another sensor. There are wiring diagrams and pinouts online at ozvolvo.org and the web archive.

You say you have spark. Since it doesn't fire with starting fluid, you either have no compression, or, the spark is occurring at the wrong time. What kind of compression values did you get when you tested it? Do you have a timing light to check the timing? It should be 10 degrees BTDC. It only takes skipping the timing belt 2 teeth to keep the car from running. You can still have spark, fuel and compression, yet, it won't run.

If there was any spark at all. Even with the timing being wrong. Youo would still get a puff or two as the fuel in the cylinder ignites at the wrong time.

With all the testing. You have most surely fouled the plugs in there with gas. I would suggest verifying the firing order on the cap and plug wires. From what I read there isn't any spark getting to the cylinders. If everything checks out including the timing belt. A compression test as suggested is needed.

Okay. Physically verified the timing as well as I can w/out pulling the accessory belts and removing the lower cover. Cam and Crank are definitely aligned. Distributor rotor looks like where it's supposed to be, as well as you can tell without seeing the timing mark. I also swapped wires and dizzy cap from my other wagon, verifying firing order at the same time. Same result, at first it didn't want to crank, but we had quite the snowstorm and there was some in the bay. Then it would crank and crank, after a couple of times cranking it resumed light dieseling after turning the key off.

The compression test I'll admit I half-assed. It was cold and ****ty out. Cylinder 1 was 120 with air noises because I didn't get the hose threaded in properly. 2 and 3 were 180. And I couldn't get the hose around the AC part on the firewall for 4.

Is it more likely that something is causing the injectors to flood the cylinders, or that something is preventing the spark from completing or being strong enough to catch? I haven't verified spark the last several times I've worked on it, since it was one of the first things done way back when I got it.

Bonus, this is what was coming down when I was working on it on Sunday, and what I had to shovel off to do stuff today.

Clear flood. Disable injectors. Brake cleaner. Start?


Click my sig.

a) ^^ do what Z said
b) Check Cam and Crank gears in correct position
c) Verify position of cam lobes
d) Verify the rotor lines up to notch

http://www.lcengineering.com/LCNewsletter/2013/JULY/1stready.jpg (disregard firing order but note rotor and notch position)


- LH 2.4 or LH 3.1 ?
- 1993 had both (2.4 AMM has six pins, 3.1 has four)
- PO installing flywheel incorrect is a problem, but do above tests first

Something it seems no one else has asked... Flywheel or driveplate installed correctly? If a rear main seal was done and the car didn't start afterward, possible the CPS is getting the wrong timing. Also, is this car a M47 or Aw70 car? That'll help us verify what version of LH-Jet it came with. 88 or 83 engine code in the VIN will be LH 2.4, whereas the 82 engine code is LH 3.1.

He said the PO was driving it and it stumbled to death. Who knows if that's true though.

You need to put it back together then verify spark at the plugs themselves. 120+ compression is easily enough to start.

To me it sounds like fuel pressure/delivery problem or timing. You say it stumbles which means there SOME form of ignition going on. Let's say the previous owner was lying and the car actually sat for a few years, you could have clogged injectors from varnished fuel.

Given your snowy working conditions, I'd try:

1) Visually check spark during cranking -- see 1st picture in ZVOLV's No Start thread. Make sure it's firing consistently and rapidly (10ish times per second) and not intermittent. If it's intermittent, try replacing the ignition module.

2) Check timing with timing light during cranking -- should be 10deg BTDC

3) Measure voltage on + or blue wire on coil with key on and during cranking -- should be +12volts. If voltage drops out during cranking, the ignition switch is suspect.

4) As a long shot, try rotating the spark plug wires by one tower, crank, rotate another tower, crank, etc. Just give it a brief crank -- if it backfires through the intake, it can cause damage. [This step shouldn't be necessary if the timing belt, disti, and plug wires are known to be properly aligned.]

5) I'm hesitant to suggest pulling the injector rail to verify fueling due to the risk of fire -- do so at your own risk. First, unplug and tape off the +/blue coil wire to prevent any errant spark. I've had good luck using plastic sandwich bags wire tied around the injectors to collect a small amount of gas while cranking.

Try 2 sparks per second. The starter turns the engine approximately 250 RPM. 1 impulse every 2 revolutions. 125/60=2.083.

2manyturbos said:

Try 2 sparks per second. The starter turns the engine approximately 250 RPM. 1 impulse every 2 revolutions. 125/60=2.083.

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ZVOLV's writeup (with cleanflametrap's picture) is for checking the wire from the coil, which fires 2x per revolution, but you bring up a good point that the OP might as well check for good spark at all 4 plug wires just to make sure that spark isn't getting lost between coil and plugs.

One more idea - check that the rubber in the crank pulley hasn't started separating, causing the outer timing marks to shift and no longer line up with the crank. If the PO tried to re-align a seemingly slipped timing belt, it might now be misaligned. A dowel through #1 spark plug hole with timing pointer on TDC would check this.

bobxyz said:

ZVOLV's writeup (with cleanflametrap's picture) is for checking the wire from the coil, which fires 2x per revolution, but you bring up a good point that the OP might as well check for good spark at all 4 plug wires just to make sure that spark isn't getting lost between coil and plugs.

One more idea - check that the rubber in the crank pulley hasn't started separating, causing the outer timing marks to shift and no longer line up with the crank. If the PO tried to re-align a seemingly slipped timing belt, it might now be misaligned. A dowel through #1 spark plug hole with timing pointer on TDC would check this.

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That makes sense. I initially check for spark at the coil. In this case, I would check at the plugs as well. I have seen spark plugs that will barely fire if they have seen contaminated fuel.

bobxyz said:

ZVOLV's writeup (with cleanflametrap's picture) is for checking the wire from the coil, which fires 2x per revolution, but you bring up a good point that the OP might as well check for good spark at all 4 plug wires just to make sure that spark isn't getting lost between coil and plugs.

One more idea - check that the rubber in the crank pulley hasn't started separating, causing the outer timing marks to shift and no longer line up with the crank. If the PO tried to re-align a seemingly slipped timing belt, it might now be misaligned. A dowel through #1 spark plug hole with timing pointer on TDC would check this.

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Will do. I'm hoping to get out on Sunday to try clearing the cylinders and starting on ether, then your five steps.

I did physically check the timing and the marks (excluding the dizzy pulley) on Tuesday. Both cam and Crank were aligned properly, and the dizzy rotor looked in the right spot. I also checked that the crank with a dowel and it was approx tdc at the mark.

I know I have fuel from the plugs, and the noid light suggests the signal is coming in in pulses. My question (I think) is whether I have leaky injectors, or weak spark. I seem to have eliminated most of the other variables to my understanding.

Or maybe some idiot shop did a clutch and installed the flywheel wrong and its just been passing hands until now. A local guy I know needed three tries and two shops to get it right, the last of which borrowed a bentley to get it right.

^^^ sounds like a good plan, you may be able to skip some steps based on your latest report. Unplug the injectors if you're using starting fluid or testing spark.

The way I interpret your results is:
- dowel through #1 spark plug hole confirms that crank pulley TDC pointer is correct.
- cam alignment marks at TDC, and good compression, confirms that the timing belt is OK.
- disti rotor alignment at TDC with #1 cam lobes pointing up means that spark at TDC will go to the correct cylinder (assuming spark plugs wires are in the correct order).
- [still to be re-verified] timing light firing at 10deg BTDC means that 60-2 flywheel alignment is good since spark is generated at the correct location. It also means that the CPS and EZK are at least partially working.

Tip:

Set crank to TDC. Use the notch on the crank washer, NOT the crank pulley. (Top timing cover removed and look down in there)

The gap in the flywheel holes should be at the starter.

Now, rotate the crank 180, remove the lower "flywheel shield" and the gap should be 180 degrees out from the starter!

mrak said:

...
I did physically check the timing and the marks (excluding the dizzy pulley) on Tuesday. Both cam and Crank were aligned properly, and the dizzy rotor looked in the right spot. I also checked that the crank with a dowel and it was approx tdc at the mark. ...

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One tooth off, I think, combined with someone defeating the locating insert on the dizzy bolt can make for crappy spark at various ezk advance settings. The chopstick in #1 is accurate to much less than one crank tooth - very sure way to get TDC.

You can get the I-shaft sprocket alignment without pulling the lower belt cover by counting teeth.

mrak said:

...
Or maybe some idiot shop did a clutch and installed the flywheel wrong and its just been passing hands until now. A local guy I know needed three tries and two shops to get it right, the last of which borrowed a bentley to get it right.

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Automatic?