2001 V70 Crank no Start

[01_Nautic_V70]

OK, it's getting weirder. It starts, briefly.

I removed the fuel rail slightly to see if I'm getting any spray from the injectors. Removed the two screws holding it into the intake and pulled one end out enough to see the injectors' spray. I also have the over-engine intercooler tube disconnected at the moment.

It starts. Surges between 1,000-2,000 rpm. Loud sucking sound as the engine grabs air from the open holes in the intake. It runs seconds to minutes, chugging like a tractor (and burning the oil out of the cylinders.)

So, I think the problem I'm really having here is that the engine is air-starved. It's getting fuel and spark. Timing is OK enough to let it run. So, where do I look next? Blockage in the air intake path? How would anything get past the air filter? The ETM not opening enough? The MAF lying to the computer about air flow or temperature?

Ideas?

[abscate]

Lets try disconnecting the MAF and then starting.

A turbo will run really lousy with a induction leak, so thats no surprise. Button everything up tight, really tight, disconnect MAF, and give it a try.

[01_Nautic_V70]

It's running (rough) as we speak.

Buttoned up the fuel pressure rail and intercooler tube. Unplugged MAF. Started. Let it idle for a few minutes. Plugged MAF back in. Smoothed slightly, but still rough. Tempted to take it for a drive to try to blow the oil out.

Quite a bit of smoke from the turbo. It looks like maybe I dripped some while adding through the #3 spark plug hole last night.

Check engine is on, presumably a disconnected MAF message. I'll swing by and have the code read at the tail end of my drive maybe?

[abscate]

If you have any leak at all in the induction, you would swear you need a new engine. Its not sexy, but the only way to confirm good induction is to remove every piece, inspect up close and personal, and reclamp it all methodically. You won't see by just observing a lot by watching - Yogi Berra style.

[01_Nautic_V70]

So to close the loop on this, here's what I believe happened.

Lawnmower system occurred. In trying to fix this, I followed the "oil in the cylinders" method. BUT I also tried spraying starting fluid into the MAF. The MAF didn't seem to like this.

After curing the LMS, I still couldn't start because the computer had no idea what was happening with airflow.

Disconnecting the MAF allowed it to run, but rough. It would surge and hunt badly as the computer still had to guess what was up with air flow. Cleaning the hot plate and wire with MAF cleaner fixed the fouling. I plugged it back in and also found the tube in the downstream side of the sensor to be barely on. Likely a leak. Tighten it all up and it purrs like a kitten again. No hunt or pulse anymore. No CEL generated.

Long story short, don't run a T5 for just a few seconds and don't spray starting fluid onto a MAF. And take your time.

Thanks for all the help, guys.

Total cost of repair was a set of plugs and a can of cleaner. About $45. Also, I now own a spark tester and a compression gauge. Aboutv$37. And I feel a lot more knowledgeable about the car.

[morganbryane]

So, my issue is still on going. I have check the timing marks and they and they look dead on. I purchased a scanner it is pulling a CEM-3A05 fuel pump (FP) Signal too low.

I have pulled the cover off the fuel pump relay itself and when the key is turned on, the contact on the relay does not engage and never turns on the fuel pump. I realize it only supposed to run for a few seconds, but it never runs at all because of this.

I have been fiddling around with taking readings with my multi meter. I'm getting LESS than 12 volts (it's like 11.7) from the CEM junction box for the fuel pump relay pins 1 and 2 which is the circuit that energizes the relay coil when the key is turned on. That's not enough voltage to engage the relay coil. I then connected the same relay directly to a 12 volt battery on pins 1 and 2 and it engaged the coil. So, the relay is good.

Now I've have also checked similar relays on the CEM (there are plenty of them) and I'm getting a full 12 volts from the 1 and 2 pins at key on.

Is it reasonable to conclude the CEM is bad because I'm getting less than 12 volts at the fp relay. I'm also seeing similar results with the Fog lamp relay.

Would the crank sensor be worth checking at this point? I'm looking at XeMODex they have re-programmed re-manufactured CEM for almost half the price of that from the dealer. I just have to send in my CEM and they will transfer everything to the rem unit. I am just wanting to know for sure if the CEM is really bad before pulling the trigger.

[01_Nautic_V70]

As an electrical engineer, it's hard to believe that the relay coil is so weak that voltage droop of just 2.5% keeps it from pulling in. Can you verify that, if the relay pulls in, the car will start fine?

[morganbryane]

I will try that if I can figure out how to get the relay to pull in. I guess I could wedge something in there to engage it.

I did try to jump the relay with the 1 pin and then grounding 2 with a good ground source, the relayed pulled in.
Also, thanks for helping with this.

[morganbryane]

I just jump the relay pin 3 and 5 the fuel pump kicked in and and it started. I haven't found anything to push the contact in the relay to engage it, but I'm guessing it would be the same result.

[abscate]

I would look at wiring and pin contact cleaning before a new CEM. And, a smal l voltage drop,should NOT stop a relay pulling in.

On edit - added NOT to clarify !!