Volvospeed Forums: blown_volvo850r - Viewing Profile

Swapped a functional IAC in today and still did not run. So I bought an OBD II scanner and these are the codes I got. Only three are vehicle specific.

P0141 - O2 sensor heater circuit malfunction (bank 1 sensor 1)
P0137 - O2 sensor low volts (bank 1 sensor 2)
P0131 - ???
P0303 - Cylinder 3 misfire
P0301 - Cylinder 1 misfire
P0300 - Multiple/random misfires
P0304 - Cylinder 4 misfire
P0305 - Cylinder 5 misfire
P0302 - Cylinder 2 misfire
P1507 - ???
P1505 - ???
P0336 - Crankshaft position sensor A CKT range/perf

This problem got worse with rain, and an enormous storm with several puddles driven through ended the R's ability to run. When I was under the front end securing the downpipe to the turbo, I noticed a complete sh*t job on the wires going to the front O2 sensor. We're talking wires hanging around with a couple spots of duct tape here and there. I'm wondering if some water got up in there and shorted something out. I'm also concerned about the crankshaft position sensor, although I'm not exactly sure what that code means. If anyone could explain the codes as well as define the three 1-x-x-x codes, I'd appreciate it.

Okay, got some slight updates. For starters, the downpipe was not well tightened down to the exhaust flange. Two of the three nuts were loose, and the bottom stud didn't even have a nut on it. The guys that swapped the motor really half-assed the job. Anyway, I put another nut on there, tightened them down really well, then pull the CBV. The diaphram looked fine, but I put a blanking plate over it anyway just to prevent future leakage. Still didn't run.

Now, here's the weird part. I unhooked the IAC and started the car. It still had a rough idle, but the boost gauge was reading 18-19 inches of vacuum, and it held there until I reconnected it. As soon as I hooked it back up, the vacuum went back down to 4-6 inches. After several restarts to get the engine to operating temperature, unhooking IAC would cause the motor to stall. Hooking it back up would still read very low vacuum and it would keep the rough idle for a minute or two, then stall.

Any conclusions from that?

I've double checked all the turbo hosing and it's all in good shape and all the clamps are well tightened. The gasket maker is only temporary until I can get to the dealership and get some new gaskets. I've let it cure all day so I'm gonna go out and start poking around again.

I noticed when the car is idling a lot of noise is coming from the IAC, if that means anything. More to come later.

Well I just got back in. I basically took the entire area around the TB/IAC apart. Removed the vacuum tree, TB, IAC and hoses, fuel rail, etc. I tried to take the intake manifold off to check the gasket but the lower bolt on the passenger side just under the port to cylinder 5 was completely inaccessible, so I retorqued all the other manifold bolts down really well. I compared the TB from my first engine and it had definitely been ported/polished. It also had a TB spacer on it, and I wasn't sure about how that worked. I know with a ported/polished intake manifold, you need a ported/polished TB or a TB spacer, but I have never heard of using both at the same time. Anyway, the TB was shutting fully, so that was not an issue. The TB gasket appeared to be pretty worn around the edges, so I went Advance Auto to get some hi-temp gasket maker. I'll be putting some in tonight and finishing up in the morning. I also noticed the gasket for the vacuum tree was completely worn out, or whatever was used for the gasket was virtually gone. So I'm gonna seal that up really well as well and let it sit overnight with the TB sealant.

Is it possible to check the IAC's functionality? I've tried running my car the way it is without the IAC hooked up and it died instantly. I'm wondering if the IAC isn't working, even though the inside piece swivels like normal.

Zappo, on 18 August 2009 - 03:30 PM, said:

Yes. My HG blew in about 20 places and oil filled the coolant. Since I had previously had a very small coolant leak in the radiator, I was an idiot and used some stop leak in coolant. I learned my lesson on that. But anyway, the stop leak dyed the coolant brown so I didn't know when there was oil in the coolant. The head was off by .015" and the coolant lines through the block were completely sludged up and couldn't be cleared out, so only replacing the head wasn't an option.

I did some more research on oil in coolant and coolant in oil and saw some pictures. Definitely isn't coolant in the oil. The bubbly mixture I saw still looked like oil, not like a foamy chocolate milkshake. Plus, there's no oil in the coolant, so for now I'm ruling out a blown HG. I do have a coolant leak, but it's from where I replaced the upper heater hose and it didn't seal up too well in the firewall, which is another problem in and of itself, but it's taking a backseat for now.

There WAS water in the tank, and a fair amount. When I drained the tank, I hooked my old fuel filter up to the line, then clamped a siphoning hose to the front of the filter and ran it into a gas can. Once I could no longer get anymore fluids out, I unhooked the filter and drained it. Probably got a half cup of water out. Then I mounted a catch can under the fuel hose and pumped another cup or so out murky brown water out. It didn't fix the problem, but at least I was able to eliminate the water in the tank as the cause of the problem.

The injectors are clean (350cc whites), the IAC is cleaned out, and all the IAC hosing seems to be in good shape.

When the car was idling and I was poking around under the hood, I did hear a low pitched whistling sound coming from somewhere near the vacuum tree/intake manifold. So even though all the vacuum hoses seemed fine, I'm suspecting a vacuum leak, and a pretty serious one. I've had bad hoses that brought vacuum down to 12-14 inches at idle, but nothing that pulled it down to 3-5 inches. I'm suspecting either the vacuum tree itself is cracked, has a bad seal on the intake manifold, or that the intake manifold is cracked, loose, or has a bad gasket attaching it to the head.

I talked to my mechanic in Louisville and he told me to try a few things to eliminate air delivery and fuel delivery. For air deliver, unhook the MAF. If it idles in a closed system, it's the MAF. As soon as I unhooked it and started the engine, it died. Then he recommended spraying ether into the intake manifold to see if it ran okay with direct injection. It didn't, so I ruled out a bad fuel delivery, but I still wanted to clear the water from the tank.

When I started the car, it revs up to 1300rpms or so and gets a full 20-21 inches of vacuum. Within a few seconds, the rpms drop to 600-700 and the vacuum pulls back to 3-5psi and holds there as it gets an extremely rough idle and finally dies in a couple of minutes. Like I said, I can hear a very muted, low pitched hissing sound at the TB area of the intake manifold, so I'm gonna pull everything out there and check it. If it ends up being a cracked manifold, no biggie. I still have the ported manifold from my first engine I can install. I'm gonna go out and get started and post up later, hopefully with some good results. It is possible the IAC isn't working, and if that's the case, well then I think that would be the problem. When I took it out it wasn't dirty and there were no hangups, but then again, it might not be working. I have no idea how to check its functionality though.