98 V70 stalled, now no start

mdamron · Post by **mdamron** » 29 Oct 2010, 15:10

Started up my 98 V70 to run some errands the day before yesterday, and as I backed out of the drive, it started running quite rough and stalled out. It acted as though it was out of gas. The tank was a bit low, so I got some gas and added it. No start.

OBD-2 through a P0103 code, "MAF sensor detecting a high amount of air flow". Cleaned MAF, still no start. I've checked for spark and fuel. Both are present, but there's still no start... it turns over, but just won't ignite.

Would a bad MAF sensor prevent the engine from starting? I've checked resistance on the crankshaft position sensor, seems to be in spec. Everything looks ok with the camshaft position sensor, but I'm not positive on how to test it..

I'm running out of ideas (short of a bad ECU) and any suggestions would be more than welcome.

Thanks!

Post by **jblackburn** » 29 Oct 2010, 15:34

It could. When mine went, my car would start, run terribly rough, sputter, and die. Then I'd have to floor it and crank forever to get it to start again.

Unplug the sensor entirely and see if it runs. The engine will run on a "best guess" estimate.

mdamron · Post by **mdamron** » 30 Oct 2010, 08:52

Update: I've disconnected the MAF sensor, and still no start... Any other ideas on what would keep this guy from starting?

Post by **jblackburn** » 30 Oct 2010, 09:45

Your engine might actually be flooded at this point; since you are getting both spark and gas, there shouldn't be anything else keeping it from starting.

Leave the MAF sensor disconnected for now, hold your foot to the floor and crank the engine for ~45 seconds. It's mean to the starter, but don't let up if you notice the engine noise change like it's going to start. These cars are prone to "lawnmower" syndrome, where the rings get washed down with gasoline and the engine loses most of the compression it needs to run.

mdamron · Post by **mdamron** » 31 Oct 2010, 15:34

Alright... I've kept the MAF sensor unhooked for a couple days now. Today, I tried holding the key in the start position for a pretty long time. The car acted as though it was going to start twice, but now... after all the failed startup attempts, the battery is pretty much dead. I suppose I'll either have to charge it or replace it. I think it's getting pretty old anyhow...

Is there any way for me to test the ECM/ECU from home?

Volgrrr · Post by **Volgrrr** » 31 Oct 2010, 22:19

mdamron wrote:Alright... I've kept the MAF sensor unhooked for a couple days now. Today, I tried holding the key in the start position for a pretty long time. The car acted as though it was going to start twice, but now... after all the failed startup attempts, the battery is pretty much dead. I suppose I'll either have to charge it or replace it. I think it's getting pretty old anyhow...

When this happened to me, I took the battery out and made sure it was fully charged then connected another spare, fully charged, battery to it to assist in the cranking of the engine.

Push the accelerator right to the floor and make sure it is held to the floor during the attempt to start your vehicle.

As jablackburn advised, once you start, KEEP GOING.

You will be tempted to give it up thinking about the hiding the poor old starter motor is getting - but they are made of pretty hardy stuff. It took my wagon about 85 seconds of cranking, if I remember correctly, before it made the first attempt to fire and another 45 seconds or so of cranking before the engine eventually fired, coughing and spluttering into life, much to my relief.

Then ease off the pedal a bit but don't let it stall as it is tries to clean out all the unburnt fuel that had built up in the engine. When you fell confident, let the revs drop towards idle. Providing everything else is O.K, it should then idle with no problems.

My wagon has done this twice since I bought it.

jablackburn could be correct about the rings, but I understand it is to do with a hydraulic valve lifter that has gone 'flat' (i.e the oil has, some how or other, escaped out of and drained the lifter of oil) and the engine needs to be cranked until the circulating oil pressure builds up sufficiently enough to pressurise the errant valve lifter which will operate the valves again and allow the cylinder to compress once again.

Is there any way for me to test the ECM/ECU from home?

This is a bit beyond my area of expertise, but I rather think not. If you know anyone with the same model as yours, see if they are willing to let you substitute your ECU with theirs to see what happens.

Good luck!

Post by **cn90** » 01 Nov 2010, 07:06

Same thing happened to my 1998 V70.

1. Whatever you do, use only BOSCH Air Mass Meter. About $160 at eeuroparts.com

2. Leave the MAF disconnected.
Fully charge the battery.
Your engine is prob flooded from the multiple start attempts, so sometimes removing the sp plugs to dry the cylinder helps.

Post by **jblackburn** » 01 Nov 2010, 07:15

Put about a tablespoon of oil down in each cylinder, replace the spark plugs, and then repeat the cranking with your foot on the floor once it's charged up again.

mdamron · Post by **mdamron** » 01 Nov 2010, 11:22

Excellent news my friends! Today I added 2oz. of Sea Foam to the gas in the tank, kept the MAF unhooked and after ~50 seconds of grinding, my little wagon came back from the dead. There must have been a touch of water in the gas can I used to refill the tank... ugh. Just to test things out, I plugged the MAF back in with the engine running - instant cutoff. So that's it! bad MAF sensor, and water in the gas my engine was flooded with.

Thanks so much for all the help, everyone! This site is truly great!