Oh boy where do I begin?... Well, my car has had trouble starting, at one point it would only run with my foot on the throttle. I had the IAC (?) cleaned and it fixed the problem for awhile. But now it won't even start. I turn the key and it seems like it wants to start but just can't get that last kick to turn on. My dad changed the spark plugs because those were blacked out, among other things. Reading other threads it points to the fuel pressure regulator.
Can anyone explain how I can check to see if this part needs to be replaced? Or have any other ideas of a possible problem?

Thank you!!! .... 2002 S40

 

I just had a simular situation with someone's 850. A car needs 4 things to start and run, fuel, spark, air and compression.

You didn't give much information on your car. How many miles does it have? How has it been maintained? Has it been smoking? Did this happen all the sudden? It could be a number of things.

The car I worked on yesterday had NO compression in #3 cylinder, besides the plugs being fouled, dirty and out of gap. It has either a burnt valve or bad piston. Oil looks like it has 20,000 miles on it.

 

It has close to 145K miles. It used to be my mother's car, and my dad kept it well maintained with all the usual. I've had starting issues for a few months now, a month ago is when we cleaned the IAC because it only ran with the foot on the gas. And then 2 weeks ago is when it wouldn't start at all. For about 2 months, it was also struggling to shift gears. It hasn't been smoking.

Not sure if this is related... The temp does run high every now and then, like right at red. And the engine fan stays on for a while after i turn it off. Changed the thermostat. My neighbor said it needs a new coolant temp sensor.

We ran a code scanner, idk the exact codes, but I do know it was a misfire in cylinder 1 & 3. I can double check again and post it.

 

Double check the codes and post them


all the points rspi has pointed out are spot on.
It could be anything not letting it fire.
Without a code we can only guess,

 

The fuel pressure regulator is checked by looking at the fuel pressure. You need a special tool for this. Harbor freight tools sells them for $15. Other signs are leaking fuel from the vacuum port on the FPR.

Have you checked the fuses? Amazing how those little suckers have caused massive headaches when one does not look there first. Especially check the fuel pump fuse in the engine compartment.

 

Coolant temp sensors are a big part of a car starting and running smooth. A lot of people change them when they change the thermostat. If it's not reading correct at start up, it's telling the computer the wrong temp and the computer is making the car run to rich or lean. Change that ASAP.

 

Here are the codes:
P0128 coolant temp below thermostat, regulating temp
P0301 cylinder 1 misfire detected
P0304 cylinder 4 misfire detected
P0118 engine coolant temp circuit high input

 

Have you cleared the codes and then tried re starting?
If so are you getting same codes? are the codes stored or pending?

Your original plugs where blacked out, with oil or soot?
Black sootey plugs can be caused by a bad temp sensor. Its running rich

Are all coil packs and plugs working? remove plugs make sure there are no cracks or damage, test every plug and coil pack to see if it sparks with a plug installed, earth to clean metal on the head and crank .Use grips to hold.

You usually test the temp sensor by testing the resistance across the terminals at different temperature ranges.whats the actual model of car/engine code etc.
I will have a look to see if i have the correct test procedure readings.

Meanwhile post the ohms readings you have from your sensor cold to warm.
You will have to remove the sensor and dip it in some warm/hot water keeping the terminals dry to see the difference in readings you should get a high to low reading cold to hot. if there is no difference or they are not to the correct range then its probably time for new one.see this site
Fuel Injection Technical Library » Engine Coolant Temperature Sensor (ECT)

 

We had the same problem we changed the catalytic converter and that fixed the problem

 

UPDATE: so my bf removed the back seats and got to the fuel pump. It ran when the car was turned on so that was good. He changed the fuel filter and after a few it started up. But then it only ran for a few minutes and shut off. Now not wont start again.... Will look into other things tomorrow.

 

S60 T5 MY2005 - 155,000kms

My misfire problem is a bit complicated... i change new volvo plugs, misfire at cyl 1 still ... After switching coil... misfire still at cyl 1. The below is data from VIDA after 10 minutes drive When the car in idle... i can hear the "pop ... pop.... pop... " softly...


Parameter Value
ECM-Misfire counter 49
ECM-Misfire counter 1 (5 cyl) 193
ECM-Misfire counter 2 (5 cyl) 1
ECM-Misfire counter 3 (5 cyl) 0
ECM-Misfire counter 4 (5 cyl) 1
ECM-Misfire counter 5 (5 cyl) 0
ECM-Fuel pressure 399.00 kPa

Please help to provide guideline to troubleshoot.

 

Keng, you should start your own thread.

 

Not sure how I missed this but if it's been running hot chances are the head is warped and compression is shot.

Please update up.