|
|
|
Mechanic read codes with generic reader--#300 and 301, which says #1 cylinder is shorting, which is obvious and unrelated, because the plugs were fouled. Volvo Houston said no, it wasn't the fuel rail pressure sensor (which fluctuated from 396 to 9 kpa, whatever that means), and so had to be further up the line, i.e. the fuel pump. Failing fuel pump would cause rich mixture by over pressurizing the system causing the injectors to insert too much fuel? Doesn't sound logical to me. Volvo Corvallis Master Mechanic said no, not fuel rail pressure sensor, not O2 sensor, nor vacuum line break. He was at a loss. I walked out no wiser than when I walked in. Are those fuel pressure parameters, 396 to 9 kpa within spec limits? Would a failing fuel pump cause this much variation, or is this normal from say idle to race? Nor would a failing fuel pump over pressurize the system, would it? I don't understand why this so called sophisticated OBD-2 diagnostic system only kicks codes as an after effect (shorting #1 cylinder) and not what's causing the initial too rich mixture, but codes #300 and 301 were the only ones the reader showed. Dick
|
|
-
|
|
|
Goatman replied:
IMPORTANT RECALL NOTICE
May 25, 2007
To all Volvo Retailers and Employees:
RE: Recall 181, certain model year(s) 2003-2004 S60/V70 Fuel Pressure Sensors
Volvo Cars of North America, LLC (Volvo) has notified the National Highway Traffic Safety
Administration and Transport Canada that we will perform a Voluntary Safety Recall to replace
the Fuel Pressure Sensor on certain model year 2003 and 2004 Volvo S60/V70 vehicles.
The fuel pressure sensor (FPS) located on the left side of the fuel rail, may at times transmit
incorrect signals regarding the fuel pressure to the Engine Control Module (ECM). If the signal is
outside of the pre-programmed allowable limits, a Diagnostic Trouble Code (DTC) may be set
and the Check Engine Light (CEL) will come on.
Engine misfire may occur during driving that in turn can reduce the engine torque, in the worst
case scenario the engine may stall without warning.
--
Always willing to listen, just not able to take direction.
|
|
-
|
|
|
Why on earth is the dealer using a generic reader? If you had to pay them for their time (I'm sure you did) they should have a volvo scan tool to tell you the exact codes. The 300-301 codes don't tell you a whole lot since you're running much too rich.
Anyway here's the list of causes for 301 (from Volvo):
-Defective spark plug
-Blocked / leaking injector
-Uneven compression
-Air leakage
-Faulty fuel pressure
-Low fuel level
-Water in the spark plug wells
-Contaminated or incorrect fuel
-Repeated cold starting where the engine coolant temperature (ECT) has reached normal operating temperature between starts
-Poor fuel quality (summer fuel in winter).
I don't know how they got the fuel pressure numbers. 396 is just slightly high (line pressure should be 375-395, so 396 is within gauge error, probably). Check residual pressure, turn off car and wait 20mins if the fuel pressure is <200kPa you've got problems..
Are ALL spark plugs the same? If not, try switching ignition coils to eliminate any of them from not sparking which causes this.. If so, what is fuel trim at? If its been enriching the fuel mixture a lot then you have O2/MAF/Vacuum leak problem.
AFAIK a 'failing' fuel pump that is putting out too much pressure comes from the pump not knowing when to shut-off, meaning it keeps building up pressure (the pump can put out 450+kPa). However, it isn't as common for the 'shut-off' to fail as it is for the pumping mechanism to fail..
--
If you're not driving it "like its stolen," are you really driving?
|
|
-
|
|
|
Tmannion--the car wasn't taken to a dealer (the nearest is a hundred miles away). A mechanic came up to my sis's house with some kind of scan tool and read the codes. He spent about half an hour hooked to the engine, getting data from it. I would certainly like to have seen her car at a Volvo dealer, but she lives in Lewiston, Idaho, and the closest is in Spokane. No way to get the car there except on a trailer, which sounds kind of stupid, given all the so-called on-board diagnostic systems. Thanks so much for your input! Dick
|
|
-
|
|
|
FWIW your car is not an OBD-II car, but a CAN car. Not sure if your mechanic's reader was a CAN reader or not but using a CAN scanner you might get more info.
It sounds to me like you're going to have to do some research or spend some money at the dealer.
Where did your fuel pressure numbers come from? An actual test? Or where they read from the fuel computer's history or something like that? If the latter those numbers are probably useless, except for the very low one which is much too low. I suppose these low numbers could point to a failing fuel pump.
Are the codes the P code numbers? If so here are the code descriptions:
P0300
http://www.obd-codes.com/p0300
P0301
http://www.obd-codes.com/p0301
The codes may not be unrelated - you may have coil problems. It's worth doing KlausC's bait-and-switch routine to try to isolate a particular coil. Also inspect the housings closely for cracks.
Some new plugs might make this process easier. It'd be nice to find somewhere that was having a plug sale and just buy the cheapest plug available with an eye to putting real plugs in later once the problem is found. Some people have good luck cleaning and re-gaping too.
Despite the one mechanic's attestation that it's not a vacuum leak, I think I would still have it smoke tested for leaks in intake and exhaust.
You can bench test O2 sensors. Do some reading on that.
I expect your car has a MAF of some kind, which can probably be bench tested. There are some writeups on MAF testing on the P1 cars on this forum and others.
Your MAP could be bad - no idea how to diagnose.
Your ETC could be bad too. There should be a way to bench test this as well, but it will require some fairly serious work to pull it out as it's probably either installed into the thermostat housing or actually a part of the thermostat itself...
I hope you figure it out.
--
1998 V70 AWD->FWD Turbo 200k+
|
|
-
|
|
|
The 396 to 9Kpa equates to 58 to zip PSI. Is the pressure regulator dying? Does the 2004 even have a pressure regulator? 58psi would flood your engine, easily, unless you are doing 6,000 rpm under load.
I do not have an answer, your car is too new with too many computers.
Klaus
--
Always willing to listen, just not able to take direction.
|
|
-
|
|
|
IMPORTANT RECALL NOTICE
May 25, 2007
To all Volvo Retailers and Employees:
RE: Recall 181, certain model year(s) 2003-2004 S60/V70 Fuel Pressure Sensors
Volvo Cars of North America, LLC (Volvo) has notified the National Highway Traffic Safety
Administration and Transport Canada that we will perform a Voluntary Safety Recall to replace
the Fuel Pressure Sensor on certain model year 2003 and 2004 Volvo S60/V70 vehicles.
The fuel pressure sensor (FPS) located on the left side of the fuel rail, may at times transmit
incorrect signals regarding the fuel pressure to the Engine Control Module (ECM). If the signal is
outside of the pre-programmed allowable limits, a Diagnostic Trouble Code (DTC) may be set
and the Check Engine Light (CEL) will come on.
Engine misfire may occur during driving that in turn can reduce the engine torque, in the worst
case scenario the engine may stall without warning.
|
|
-
|
|
|
Good work, Kyle!!!
But, she is a long way from a dealer...
Klaus
--
Always willing to listen, just not able to take direction.
|
|
-
|
|
|
Klaus--thanks for your input! It's looking more and more like the fuel pressure sensor or the fuel pump. I don't think it's a cracked coil. Were that the case only the one cylinder would be fouled, and I think the mechanic said all the plugs were starting to carbon up, with #1 cylinder obviously being the worse because it kicked the two p.o. codes 300 and 301. Think I will telephone the mechanic at this point and get more comprehensive data than what my sis has fed me over the phone. Thanks again for your input. Dick
|
|
-
|
|
|
jadnhm--as far as I can tell from talking to my sister, the kpa data was freeze frame data, which I assume means was read directly from the computer as the car was running. The home mechancic though could have read the fuel pressure directly using a pressure gauge, if the fuel rail has the bicycle valve on the end like my 850. Will check with her. Thanks for taking the time to reply. Dick
|
|
|
|
|
