zerMATT951

So the car has been running great since my rebuild completion in September/October... until this morning. I got up early and dropped my daughter off at daycare, and when driving back to the house (to tear into my brother's car today!), the engine stopped suddenly a block from the house. I was (and had been) pretty much idling into the neighborhood, maybe 1,500 rpm, and it just died. I hit the clutch and took it out of gear quickly... coasting. Engine oil temp was just warm at 140-150 ish, coolant was up to temp (the normal low-temp white mark). I tried to crank it while rolling and the starter wouldn't turn the motor over. I believe oil pressure was ok as there were no warning lights before it died, and I had just topped off the oil a few days ago.

I get back to the house and pull the plugs - nothing looks or smells odd there. There is no oil or coolant leaking from anywhere, no smoke, no steam. I tried to crank the engine with the plugs out and it will crank SLOWLY, but it's straining.

The ONLY thing that I've done differently was about two weeks ago I changed the FQS switch to position 2 to remove 3% of fuel. I did this because the AFR's were running in the 10.7-11.0 range at WOT. The FQS change helped my AFR's at WOT (11.1-11.5 now), but they also increased AFR at idle to 16-17, and sometimes higher. Could the lean at idle have caused a cylinder to lock up when idling slowly into my neighborhood?

I did check exhaust header temps as soon as I got home - they were all equal but I forget the numbers. I also measured cylinder head temps near the plugs, that was all equal too.

What should I do next? Pull the belt covers and try turning the engine by hand? Should I spray some lube into the cylinders and crank it to see if it cranks easier? Should I just pull the head and see what things look like first-hand?? Geez...

carlege

Electrical issue?

Clown

Just thinking outside the box....before you tear down the engine. Did you check the alternator or battery? Your battery may not be charging or holding a charge. Turning crank by hand sounds like a good idea otherwise.

dillon410021

sounds like battery/ alternator may have died

carlege

I would think the battery gauge would show something unless you just lost a true connection

Bri Bro

First thing I would do is check your timing marks to make sure they are still OK. A quick jumper on the battery should eliminate that as an issue. If you have aftermarket battery cable check the connectors and the fuses.

lart951

even with a low battery if the alternator is good the car dont just stop, has it been raining there?

minho78

Matt, timing marks. Speed?refernce sensor. Battery Voltage. Good Luck.

Rogue_Ant

Nope. AFR at idle can be quite a range without concern.

As others mentioned, first thing to check is battery voltage.

racerxrick

sorry to hear Matt...like everyone else my first thought was electrical. Keep us posted.

kyle951

Matt..I agree with everyone on the Battery and then I would move on to the Ref. Sensor, and then possibly take a look at the Fuel pump if the car is cranking but not turning over. This could be something simple or be something much more complex like timing.

Also, I had something similar happen to me a month or so ago and it turned out that I was out of fuel and the gauge and fuel sending unit had gone bad. This is just another thought of possibilities on what could be going on.

Kyle

jerome951

Slow cranking is almost certainly an electrical issue. Focus on things can can affect cranking speed (i.e. not the speed/ref sensors, fuel pump, etc.). Check all power and ground connections from the battery, starter, alternator, and condition of the battery itself.

zerMATT951

Ok guys - thanks for all of the input. I haven't dug into it any further yet other than leaving my charger/booster (10/100A) connected for a few hours. The car turned over very slowly at first - even with a 100A boost from the charger, but I tried again an hour ago (plugs still out) and it turned over quickly. I agree at this point that it does sound like an electrical problem, but it's odd that a dead battery could cause the car to die immediately just driving down the road.

Unfortunately, we are 5 hours into tearing my brother's car apart to try to reduce some of the massive oil leaks he's got - we will have the turbo out soon and both balance shaft covers off, then probably call it quits for the day and hopefully be re-assembling in the AM.

I'll toss the plugs back in at some point this afternoon and see what happens. If it still won't fire, I'll be checking timing marks, etc. I'll also confirm fuel pressure the next time I crank it. Maybe my Bosch "High Volume" (LR) fuel pump went out at the same time my battery died???

racerxrick

keep us posted Matt!

dillon410021

also, ,maybe the water pump seized and is preventing the motor from spinning easily