Q45 Engine won't start: any thoughts?

[bravetex]

This happened: First key start ended quickly with odd sound like the starter was not engaging flywheel. Shortly thereafter a burning rubber smell eminated from under the hood. Two more attempts to hear it just spinning, like there was no compression. With help, I observed the fan spinning (thus the crankshaft) so I deduced it wasn't starter.Seemingly, no compression. No clunking sounds (like a broken timing chain.)Battery strong. Engine turns effortlessly.It's like there are no plugs in the threaded openings.

Dont' know at this point if it's firing or not.

Any thoughts?

[maxnix]

Year? Mileage? Maintenance history?

The fan is driven by a viscous clutch. Got FSM? TSB?

[bravetex]

1994 Q45 with 152,000 miles.I'm the second owner, and the first owner fastidiously maintained it at Infinity dealer ( I have all the records.)I switched it to AMSOIL synthetic oil at 102,000 miles.AC system rebuilt, alternator replaced, and battery replaced three weeks prior to this current problem. I've never tuned it up and the plugs have never been changed.Other than that it ran perfectly for 50,000 miles, except for standard stuff like brakes, tires, etc.

Not sure what FSM or TSB is, but I'll start reading this site for that info.

[draivar]

same issue here...car running perfect until last night; this morning it just had this loud zinging noise like a bad starter...any leads?

1991 Q45 w/ TCS138,000

[texasoil]

OUCH!! Definitely not a good sign. IF the timing chains were both broken (cams not turning) then SOME of the cylinders would still have compression unless 'FATE' managed to break all the valves. Frankly I am stumped--what would/could cause total loss of compression immediately on cranking? Complete collapse of all the lifters? but ALL? and WHY?

[maxnix]

Frankly I am stumped--what would/could cause total loss of compression immediately on cranking? Complete collapse of all the lifters? but ALL? and WHY?

Failed guide pieces fouling the oil pump drive chain?

[bravetex]

It looks like the timing chain broke and bent the valve guides. That would explain lack of compression.However, that's what I was told by a mechanic who is in a complex of independent mechanics and they all agreed.I'm going to part it out.

[3Q Jay]

PLEASE give us more of a post-mortem on the engine. this would be the first 94 to my knowledge to fail of broken guides. or if it is truly the CHAIN, and not the GUIDES, then this would be disturbing as well, unless there is some physical evidence analysis to pinpoint the root. never heard of a chain letting go at that mileage, even with a fiar amount of a buse--which sounds not to be the case here.

[draivar]

Cause of my problem above???

Turned the crank pulley manually and tried to start up the car. It started up just fine so my take on this??? The starter gear has probably wore the flywheel teeth and so it slips. You have to hope the flywheel ends up on a good clean spot when you turn the ignition off. I will be out of town for the next week or so, when I return I will pull the transmission and start replacing wore off parts. Think the starter needs to go as well as a new flywheel needs to go on. There is rattling at times so something is inside there that needs to be pulled out. Car shifts fine and purrs....

[bravetex]

OK, here's what happened. I did have an early Christmas!

An infinity dealer mechanic told me it was a long shot, but there was a chance that the "hydraulic lifters" had bled down. He said that he had seen it once in his 17 years as an Infinity mechanic.

He suggested that the lifters were holding the valves open, thus no compression. And I tell you that the engine was spinning fast a freely when it wouldn't start. The crankshaft was turning, the camshaft was turning, but the lifters weren't moving the valves. The engine must have compression, fire, and gas to start.

His suggestion was to hold the gas pedal down, simulating the choke effect, and just crank the engine until the engine starts. And that it might take three to eight minutes to start.

So, the engine had been pronounced dead by timing chain suicide by five mechanics and had been down for five weeks. I was sick because I had just put 1800$ into new AC and alternator.

So I ran over to the shop late in the evening and turned it over two minutes before the battery ran down. At the last second I detected an firing event.We charged the new battery up next morning, and cranked on it for three minutes.By the Grace of God it started! Ran like nothing ever happened, like it did before, which is smooth as silk! The mechanic was duh..duh..duh all over himself.

Ok, so the lifters bled down. I still don't know what that really means, but it's the best Christmas gift of the year!

[DrewQ45]

OK, here's what happened. I did have an early Christmas!

An infinity dealer mechanic told me it was a long shot, but there was a chance that the "hydraulic lifters" had bled down. He said that he had seen it once in his 17 years as an Infinity mechanic.

He suggested that the lifters were holding the valves open, thus no compression. And I tell you that the engine was spinning fast a freely when it wouldn't start. The crankshaft was turning, the camshaft was turning, but the lifters weren't moving the valves. The engine must have compression, fire, and gas to start.

His suggestion was to hold the gas pedal down, simulating the choke effect, and just crank the engine until the engine starts. And that it might take three to eight minutes to start.

So, the engine had been pronounced dead by timing chain suicide by five mechanics and had been down for five weeks. I was sick because I had just put 1800$ into new AC and alternator.

So I ran over to the shop late in the evening and turned it over two minutes before the battery ran down. At the last second I detected an firing event.We charged the new battery up next morning, and cranked on it for three minutes.By the Grace of God it started! Ran like nothing ever happened, like it did before, which is smooth as silk! The mechanic was duh..duh..duh all over himself.

Ok, so the lifters bled down. I still don't know what that really means, but it's the best Christmas gift of the year!

Absolutely amazing... I'm so happy for you I could cry. I can imagine the relief you must feel after all that. I'd say have that dealer mechanic check the car out. Maybe as a little side-job so you can show him your full appreciation. Yes, I said it, so what?

...Drew..

[Q451990]

(duplicate from the other thread)Well, I think your tech. got the right fix, but for the wrong reason! It's very, very, common for these engines to flood during cold weather if they aren't allowed to warm up properly after a cold start and then shut down. A typical scenario is someone starts the car to move it to a different space, then tuns the car off in less than a minute.What's happening is the ECU is set up to send a very heavy hit of fuel to the cylinders while trying to start in cold weather. Esentially it's a choke - but instead of removing air, it adds fuel - same effect on the fuel mixture, but different route. But - if the car is turned off soon after start-up, all of that extra fuel is left sitting in the cylinders. Then it washes the oil off of the cylinder rings.... so compression is lost. "Flooring" the pedal during cranking is the ECU's signal that the driver thinks the engine is flooded so it shuts off injectors...

Heath