2004 V70 NA poor running, starting, head gasket? Topic is solved

Post by **abscate** » Wed Oct 10, 2018 5:32 pm

Be careful of the moderators here. Some use old engine oil.

I’m guessing the compression numbers were a bit low because the engine was cold, and the compression gauge recently read low on a T5

Plugs were gnarly and about 0.045 gap

Car started easily and idled smoothly right after plug clean and gap. No codes either, except a pending P0303 misfire, Check engine off.

There is very little , if any coolant smell at the pipe. If there is a head gasket leak , it’s very small.

What happened between then and today is the mystery to be solved.

I’m leaning to a throttle body cleaning as next step. 2004 Bosch ETM. Can you evaluate by watching the plate through ignition sequence like a Magnetti Marelli?

Spiderland · Post by **Spiderland** » Wed Oct 10, 2018 5:54 pm

Yes a mystery! But just to be clear...it was only 3 hrs sitting after plug clean and gap with good start that this started happening. And then next day with new plugs installed same thing. Just want to clarify for clue purposes...

I also had a neighbor drop off his code reader. I will check them tomorrow. Can you do this if the engine doesn't start?

YouTube · Post by **oragex** » Wed Oct 10, 2018 6:41 pm

If it wasn't the decent compression, I'd say cracked cylinder allowing coolant to slowly fill it up when parked which would cause poor start and idling. The compression test may have just cleared the cylinder, then it started just fine.
But since it had good compression - at least at the moment of testing it, I'm thinking maybe valve issue or even timng belt issue. Maybe a seizing (and leaking) water pump? Stripped crank gear?

Post by **abscate** » Thu Oct 11, 2018 7:43 am

My karmic feel is that the major mechanicals on this engine are OK, and that it is a engine management issue. I did forget to check battery voltage and condition, a weak battery on the P2 two can lead to a lot of running issues and strange behaviors. Again, very little smell actually not detectable by me,

Post by **SuperHerman** » Thu Oct 11, 2018 3:15 pm

Did you look at the piston tops when the spark plugs were removed for sign of steaming?

Did all the the spark plugs look the same? With those compression numbers they should look similar, maybe a little dirtier on 3-5.

Update us with the codes - I am thinking the coils are not plugged in well, harness issue, or one failed as a result of removal (finally gave up the ghost. Remote chance of a bad spark plug.

My original response about not driving the car was fear of coolant in the oil and possible resulting bearing damage in addition to cooking the rings. From the response this is not a concern for now. Need to figure out the over heat.

What if any diagnostics was performed on the water pump and thermostat?

Post by **abscate** » Fri Oct 12, 2018 2:13 am

Not overheating now.

Plugs looked all the same, not bad, just worn out, no sign of steam cleaning on any plug.

Coils are original, 2004 date codes. Hmmm. I wonder how many spares I have left ?

Can anyone help on the Bosch TB? Does it go through the same whine -click self test like an MM or something similar?

On review... OP has exactly the same issue as previously reported, poor running with no power , which cleared on restart. That’s pointing to poor electrical connection somewhere, maybe flaky coils at 177k miles.

Time to hit the basics

Get your battery on a charger so we have a good 12 V source. These cars hate low voltage

Check fuel pressure at rail
Replace coils, budget permitting..(if committed to keeping car, coils are probably at 90% of life)
Break and remake throttle body electrical connection
Break and remake ECM connection ( contact cleaner)
Get info on and test throttle body with VIDA

Spiderland · Post by **Spiderland** » Fri Oct 12, 2018 11:01 am

Today I will swap out coils to different cylinders and read the codes to see if it tells me anything. Will let you know what I find.

When I started it this morning, after charging the battery overnight, with the coils still in original places, it did run, albeit very rough (it did start though!). When I took it up the road a bit, it was still in limp mode. I read the codes and the first code showed misfire on 4, cleared it and the next code on 3 (again original codes showed misfire on 2 and 3). Note- When I replaced all of the spark plugs a couple of days ago, they threaded very smoothly. The wiring to the coils had no evidence of wear, that I can see at least, and seemed to seat very nicely. I do realize I might need all or some new coils. Also, it might just be my charger being wonky, but my battery charger read that it was only at 20% after charging overnight.

I will look into all the other suggestions in the above posts, but I will start with the ones within my capabilities. My awesome NAPA guy did have a suggestion- He said that I might want to check the ground that affects all the coils. Is it my understanding that besides the individual wiring for each coil there is an overall ground for the whole run of them? Would need to look at the wiring diagram, but if someone has some info for where to look it would be helpful. Does that sound like something to look into?

I also called a local Euro specialty shop and asked if they had a VIDA to diagnose. They didn't exactly answer yes, but said they have the diagnostics to give me a comprehensive answer. When I asked again specifically about VIDA, same answer. And the cost would be around $170. Should I be weary of that? My guess is yes?

Spiderland · Post by **Spiderland** » Fri Oct 12, 2018 11:26 am

Also another clue:

Even though my car had a rough start sometimes with minor vibration that abated after a minute, this new aggressive engine vibration started shortly after we did the compression test and reassembled everything. And it does not subside after warming up.

YouTube · Post by **oragex** » Fri Oct 12, 2018 11:47 am

Just do this when it runs rough, don't replace all coils just to see www.youtube.com/watch?v=nDwtZCWU7u8

The things you've touched with the compression test are the coil wiring - look closely where these get into the coil for cracks, and see if some wires are getting crushed by the plastic cover (my cover went to garbage any way, this thing only makes the coils getting hotter).

Have you cleaned the TB in and out ? (15 min job on n/a)

Spiderland · Post by **Spiderland** » Fri Oct 12, 2018 1:15 pm

oragex wrote: ↑Fri Oct 12, 2018 11:47 am Just do this when it runs rough, don't replace all coils just to see www.youtube.com/watch?v=nDwtZCWU7u8

The things you've touched with the compression test are the coil wiring - look closely where these get into the coil for cracks, and see if some wires are getting crushed by the plastic cover (my cover went to garbage any way, this thing only makes the coils getting hotter).

Have you cleaned the TB in and out ? (15 min job on n/a)

I meant just switching coils to different cylinders to check codes, not replacing as of yet.

And we have looked closely at the wire conditions. From what is visible, they look good.

The throttle body (is that what TB refers to?) cleaning sounds a bit out of my realm. Maybe not, but have never done this. Unless you mean just squirting in that cleaner and revving. That I can do...

Any thoughts on the main ground to the coil run?

I will check out the link. Thanks.

2004 V70 NA poor running, starting, head gasket? Topic is solved

Re: Coolant leaking into Head? 2004 V70