Problems (engine? transmission?) after PCV job Topic is solved

Post by **lext** » 21 May 2018, 12:23

I just did the PCV overhaul work over the last 2 weeks (the car is on ramp the whole time). It took longer because I had to order additional parts while I was in there.

Just a brief recap of what I did: drain the coolant, took out fan housing, took out a number of air vacuum hoses, took out the fuel rail, replaced the oil box and the pipes connected to it, put things together, fill up the coolant.

After I got everything back together though, a few things are not quite right:
- First of all, the moment I turned the key on, the transmission light (the one with the up arrow) keeps flashing.
- Then when I turn the key on, at first the car stuttered and will not stay at idle (engine feels like it wants to die). I have to rev the gas up to about 2K rpm for about 30-40s or so for it to stabilize, after that it idles alright. I understand this is normal, since the fuel rail was off and fuel was sparse at first.
However the next morning the same thing happened, and again I had to push the gas for 30-40s before it can idle on its own.
- Most problematic is that the gear change is no longer smooth. When I press the gas, the rev will increase past the point of normal gear change, and then there will be a "jump" when it shift to the upper gear. This happens with all the gears, so now on my drive, I'll experience a lot of these "shudders" when the gear changes.

Before I put everything back, I did make sure and check I restored all the hoses, and reconnect all the vacuum to the best of my knowledge. I also had some picture I took of the vacuum tree to guide me along. But, let's assume that I mis-connect some vacuum hose, then can the car show the symptoms that it did? To have transmission problem, and flashing arrows even before the car is turned on? I thought flashing arrow only happens when driving.

Any further tip on troubleshooting will be appreciated. I don't have the car with me right now (am at work, left car at home) so I can't pull the code yet, but will do it tonight.

Post by **lext** » 21 May 2018, 12:34

I've looked at it so much I've sort of memorized how I connect the vacuum hose now, so let me describe all my connections:
- I didn't took out the throttle body, so the two connections underneath it was left alone.
- On the flame trap there are 2 connections: a bigger one go to the oil box, and a smaller one go to the back of the vacuum tree.
- On the back of the vacuum tree (the side facing the inside of the car) there are 2 nipples. One goes to the flame trap (described above), one go to the fuel pressure regulator (located among the injectors, just beneath the fuel rail)
- On the front of the vacuum tree (the side facing forward of the car) there are 3 nipples and a big opening. The big opening goes into the air-control valve. Of the 3 nipples, 2 go to some line coming from the fan shroud, and one goes towards a T-shaped line near the battery.
On the fan shroud, there is a line going towards a small regulator underneath the intake manifold (near the air control valve, but under).

Of all the connectors, I'm positive about where each one is supposed to goes except for "which nipple on the vacuum tree does this go into". By that I mean "I know this one goes towards the vacuum tree", I'm just not sure "which nipple". However from looking at the vacuum tree, all the nipples appear to be connected and at the same air-pressure, so I assume "which nipple" isn't an important factor. But please let me know if I'm wrong.

Post by **lext** » 24 May 2018, 00:48

Well, I have a bunch of codes

I guess I'll be busy this long weekend...
Socket A1:
213: Throttle position signal too high
323: Lock-up slipping or not engaged.
Socket A2:
411: Throttle position sensor signal outside voltage range
Socket A6:
411: Throttle position sensor signal absent or faulty

Wait a minute, everything is pointing to the TPS! Maybe I just forgot to plug it in somewhere.

Post by **lext** » 27 May 2018, 02:01

To continue my story, I went out and check the connectors today. Just like the codes said, I didn't plug the TPS sensor in. Easy, right? I pushed it in, started the car, it still felt like before (doesn't want to start unless I press on the throttle). However this time I didn't leave the throttle on too long. I let off, and the car promptly died.

I went out and check again, up, down, left, right, can't see anything loose anymore. Turn the key on again, and the up arrow light is gone. Everything looks really good. But this time the car no longer wants to start. Even if I press on the throttle. It cranks well, starter motor and battery is strong, it just doesn't "catch on". I was perplexed. A moment ago it could start, albeit poorly, but now it can't.

I check the two obvious conditions, and they're good: I have pressure at the fuel rail, and I have sparks. After all, before I plugged in the TPS, I could still start it and drive, just not too well. Now it doesn't start at all. What the f?

I tried to pull the codes again but got nothing new. The old ones are still there but I think they just have not had a chance to clear. I think this has to be something so basic, sorta like dead fuel pump or something. And yet with fuel pressure and sparks, I can't think of what else to check. Ideally I would have liked to check if the injectors spit out fuel at the right moment, but how are we going to test for that?

Post by **lext** » 05 Jun 2018, 16:44

Just update in case someone comes across this in the future: I did another check of all the hoses again. Looked even where I didn't think I disconnected anything. And I found 2 hoses out, one a vacuum, one another hose in the back (near the firewall). Can't remember how they got unhinged but put them back together nevertheless. Tried again but still stuttering. Thought maybe cylinders are soaked, so got the spark plugs out to clean and dry (spark plugs have lots of carbon on them). Tried again, still stuttering. Figure battery may be weak, so put a jumper in with another running car. Tried again, still stuttering, but sounds like there's some hope (cranking lasts just a few milliseconds longer). Kept trying while varying the amount of throttle I give. Finally for some inexplicable reason the engine catches and vrrrroomm! Oh the sweet, deep, throaty sound of the 850

Car has been running great since then. Next step is figuring out how to clear the CEL...

MDK · Post by **MDK** » 05 Jun 2018, 19:36

I know that a major job you just did. If you don't have a code reader... disconnect negative battery cable for about a half hour. Sure clear unless you have another issue...

crlande · Post by **crlande** » 05 Jun 2018, 20:34

https://www.matthewsvolvosite.com/read-codes-volvo-850

Post by **Roger_850T** » 05 Jun 2018, 20:45

So now it's running great? Awesome! Some thoughts as I read through your posts...
- It definitely sounded like a pretty major air leak somewhere, so I'm glad you found some hoses amiss.
- Search for "Lawnmower Syndrome". It's a real thing, and it sounds like with the hard starting and rough running from the air leak, you got into the lawnmower syndrome situation, which caused it to subsequently be harder to start, even after fixing the air leaks. Typically they come back like yours did - rough, then it clears and runs as if nothing ever happened.

Glad it's going again!

Roger

Post by **lext** » 05 Jun 2018, 21:14

crlande wrote: ↑05 Jun 2018, 20:34 https://www.matthewsvolvosite.com/read-codes-volvo-850

MDK wrote: ↑05 Jun 2018, 19:36 I know that a major job you just did. If you don't have a code reader... disconnect negative battery cable for about a half hour. Sure clear unless you have another issue...

Yes, I'm aware of all the code procedures

But somehow this CEL eludes me. I actually created a separate thread for it since I didn't want to overload this with all the different issues.
And I did do the battery disconnection thing, but that is to no avail.
Right now the issue is that I no longer have any code on A1 and A2 sockets (used to have a bunch in the middle of my trouble), but the CEL is still on. Next I'll try to clear from every socket and we'll see.

Post by **lext** » 05 Jun 2018, 21:24

Roger_850T wrote: ↑05 Jun 2018, 20:45 So now it's running great? Awesome! Some thoughts as I read through your posts...
- It definitely sounded like a pretty major air leak somewhere, so I'm glad you found some hoses amiss.
- Search for "Lawnmower Syndrome". It's a real thing, and it sounds like with the hard starting and rough running from the air leak, you got into the lawnmower syndrome situation, which caused it to subsequently be harder to start, even after fixing the air leaks. Typically they come back like yours did - rough, then it clears and runs as if nothing ever happened.

Glad it's going again!

Roger

Yeah I was thinking something must have happened during the 5 minutes or so I ran it in bad mode. Maybe it fouled up something. Problem is the stuttering was so generic, I had to do all these checks for plugs, sparks, fuel, battery to make sure it was none of them. I even tried to disconnect the battery overnight in case the control module "remembers" something and refuse to start

The silly things we do when we don't know what is wrong...