I have just bought this car a month ago and it was running well up until a week ago when I started experiencing some misfiring and engine power loss while driving, either accelerating and even once during cruise control.
Just starts hesitating until I play with the gears and get it out of that misfire.
The check engine light went on once and it read out P0090 (Fuel Pressure Regulator 1 Control Circuit) and P0190 (Fuel Rail pressure sensor circuit malfunction) upon me taking into the dealer for an inspection they found nothing wrong with it and reset the lamp.
now it is acting up again 3 days later and even worse but no lamp this time.
They said it may be the fuel pressure regulator and I read at some other forum it could be the spark plugs and coils.
Any suggestions?

 

I've got your same problem and I registered to post it and get a response about it, but now I see no one has answered since august, so disappointing...

My engine started to misfire just after I took it to this "specialized" tuning place. They changed the OEM oil, oil filter, and spark plugs for: Liqui-moly 5w40 synthetic oil, K&N oil filter and Denso iridium plugs, they also cleaned the fuel injectors, I thought it was an upgrade worth the cash but it has been a regretful downgrade, I might as well had brought it to the dealers (which I'm doing on Monday first thing).

Since the "upgrade" the car misfires frequently (mostly on higher speeds) and the engine light comes on sometimes, but no codes, I took it to the tuning place mad as hell but after a 20 minute ride the car did nothing wrong and it didn't deliver any codes to the scanner (obviously a work of Murphy's Law!) They said that it must be the coils that are old and can't put up with such good plugs (B.S.) or that it's a problem caused because I normally use regular gas instead of premium (more B.S.) or, that is a problem I caused to the fuel pump because I'm not supposed to wait until the tank is 5 liters to empty for a refill (premium grade B.S.).

Doing a bit of internet research, I'm guessing its the new plugs that are causing the misfire, I think the gap is not right, or maybe they didn't plug the wires right? I don't know, any suggestions???

 

I hope that you aren't running regular gas. My '02 S40 ran like crap on regular gas. I won't even try it in my V50 T5.

It could be the plugs. The Volvo plugs are actually very good and there is not much need to try and upgrade.

 

Having the same problem with my girlfriend's S40 turbo. Replaced the coil on the misfiring cylinder which made a noticable difference but its still misfiring. I am gonna change the plugs tomorrow. I may try premium gas also.

 

YES! Premium Gas.

I found that the regular does not save you anything in these cars (turbo anyways). Your fuel economy goes down and the car runs like crap and will cause further problems. In the study that I did with my '02 S40, the drop in fuel economy burning regular instead of premium negated the $/gal savings.

They can run on 87 octane but they were designed for 91 or higher.

From the owners manual:
Octane rating
Volvo engines are designed for optimum performance on unleaded premium gasoline with an AKI octane rating of 91 or above. AKI (ANTI KNOCK INDEX) is an average of the Research Octane Number, RON, and the Motor Octane Number, MON. ((RON + MON)/2). The minimum octane requirement is AKI 87 (RON 91)

Stan

 

OK, so I took the car to the Volvo Dealership's Service Center and they said that for sure the "special tuning" place didn't "calibrate" the plugs, which I understand as if they didn't fix the gap on those famous Denso plugs to the size required by Volvo. Unfortunatelly, I have to wait untill they first fix a crashed back door (work of a stupid *** truck, thank you very much) for them to check the plug thing (and since all parts are being shipped from Sweden, I'm in for a looooong wait). I'll be posting results.

Now, I normally use Premium but I also use Regular. On the city, I have to be honest, the difference in performance is slightly noticeable. On the road it's another thing: the car performs much better with Premium, but still, Regular is not as crappy.

As for fuel consumption, the car gives me almost 600 km per tank with Regular, and no more than 580 km per tank with Premium. In my oil rich third world country, a full tank of Regular is around 15USD cheaper than a full tank of Premium. So, when there's cash flow and I'm thinking of taking the high roads, I always fill it up with Premium; if I'm sometimes short on the wallet, I'll take Regular. Now, I don't think using Regular sometimes (or even all the time, for that matter) is harmfull for the engine, since as stated in the manual (posted by AutoNaut above) the minimum required is AKI87. (Thinking about if Regular in Mexico is really AKI87...) Anyone thinks different???

 

I have a 2005 Volvo S40 AWD. The car has been great, but in the last couple of months the car has started to loose a lot of power. When I accelerates you can feel a thud all of a sudden, and then the acceration is minimal thereafter. In the beginning it just happened once in a while, but in the last few weeks it has started to happen more often than not. I took in my car for 30K services (I know, I don't drive much..) about a month ago. I told the Volvo dealer about my problem, but he said that it probably would be a waste of money to run it through he computer and jus told me to come back with it next time it happens, which was not very helpful... Does anyone have any good idea what it could be? The dealer just gave me a BS answer that it was probably my gasoline, but I always fill it up wih the premium grade so I can't imagine that it would be the issue.

 

Hi all,
I have this very same issue on my 05 T5 AWD. CEL came on today reading the P0193 (Fuel Rail Pressure Sensor: High Input) and a P0190 (Fuel Rail Sensor Malfunction). I have seen may post about this problem but none say a solution. Has anyone been able to correct this proble and what was the problem? Please Help, I dont have any dealers close and the closest one is terrible so I want to be sure what I need to get fixed before I take it in.
Thanks

 

Ask over on SS. There is a little more traffic over there and there's few Tech's as well.

 

I have received the same error codes as all of you, t P0090 (Fuel Pressure Regulator 1 Control Circuit) and P0190 (Fuel Rail pressure sensor circuit malfunction). Same symptoms.

I've had the fuel pressure checked, valves, changed the spark plugs (by the dealership), software upgrade, cleaned the battery terminals, ran heet through the engine about twice, and .... nothing.

The dealership couldn't figure it out either. Eventually they came to the conclusion that it was a corroded battery cable, that they would graciously change for $800. ... so, I didn't do it, because I seriously doubt its the battery cables.

In the winter it had trouble starting as well, and would flood, I had to unplug the injectors sometimes to get it started.

I really can't think of anything else, i'll clean the throttle body this weekend, and start running on premium to see if it makes a difference.

If the dealership can't figure it out, you know its a mystery. I'm starting to wonder if its a computer problem.

 

Finally got this issue resolved a month ago at a dealership in St. Louis. It ended up being a fuel sensor that was causing the hesitation/loss of power. They also found a manafold pipe that had rotted out that they thought was contributing to the issue but it still had cut out and loss power after they fixed the pipe just sounded a little better. Once the fuel sensor came in and was replaced the car has ran great. If you want to know the exact sensor ill try to look it up on the invoice. Good luck.

 

I would love to know what sensor it was, how much it cost, and if possible how the mechanic figured that out..... I want to get mine fixed as quick as possible.

 

The sensor that was causing the cut outs was a fuel pressure sensor. The only possible part number on the invoice for the sensor is 31272732 but this may be a stock number for the dealership. If there is more than one fuel pressure sensor on this year type I recommend calling this dealership West County Volvo 636-227-8303 to get the part number from the above number. The sensor wasn't cheap either at $196.47 and was on back order which makes me think this issue is happening quite a bit. All said and done it cost me $260 parts and labor which is worth it since the issue continues to get worse until the car will actually die while driving and then not start for a while. Good Luck

 

The new S40 came with the manual transmission with six speeds, an admission that we were a bit conflicting. Given the choice, we would always go flat, but the clutch of the S40 was either instant or Instant-Off, making advantage of the tide shift six-speed rare. In practice, the coupling can not control, but if you break the concentration before the light turns green to expect a shock when they leave the bar.

 

Change your fuel presure rail sensor,

 

the problem was with the turbo, and it was a quite easy fix even though I had to wait a couple of days for the part.

 

I have a 2005 S40 T5, and had the same issue about a year ago, and took it to my Volvo dealer in Milford, CT, they fixed the problem right away. They told me it was a fuel sensor chip of some sort, maybe fuel pressure chip? It was a computer ship sensor issue. They told me at times the chip would miscalculate the amount of fuel being used and lower it, causing the car to lose power and feel like it was studdering. They told me at other times it might feel like there was too much power, but I don't recall feeling that. Either way, it was fixed and runs great except for rough starts, which I need to get checked at some point. I had a 1980 volvo handed down to me in the late 80's, had all kinds of electrical issues. It seems since FORD bought Volvo, there are alot of fuel regulation chips and sensor issues going on. Overall I love volvos and will probably be a lifelong volvo fan.

Anyways, fuel has never been an issue although people love to use that as an excuse. Fuel grades have a VERY minor influence on performance. The most I ever had with cheap gas was mild and rare knocking. Once I had a temporary foul smell from the catalytic convertor (but that was a chevy I had at the time). I've never had any fuel pump issues. Never any engine issues. It's ALWAYS been the computer or sensors that gave me problems, well... the two problems I've had in the past 6 years.

 

can anyone please help. coming back from bournmouth doing 70mph suddenly the car slows down and the message flashes up reduce speed service required. then traveling along at aboat40mph. then comes to a junction stops then tries to excelerate away it takes a few seconds to do so. its been in the garage for 2weeks now they said its the computor so they send it away to bosh.bosh say there is nothing rong with it. its a 2,5 tdi v70 2000 please help. ernie

 

Try over in the V70 forum. Maybe someone has had the same problem.

Not to run you off, just that us S40 owners would just be guessing at a diesel.

Unless someone here has experience with this?

 

I have an 2004 S40 T5 with the same problem, reading codes: 208C:-fuel pressure sensor interruption/signal too high, 209B:- fuel pressure sensor signal improbable.

I replaced the fuel rail pressure sensor, and it is a very easy fix.

The fuel rail pressure is on the top left corner of the engine below a plastic cover, just to the right of the cam belt, and below the oil cap. It is secured by one (yes only 1) torx screw. #WARNING# Ensure you hold a rag over the sensor whilst removing it as the rail will probably be pressurised, I'm sure there's a bleed valve somewhere but I'm not sure where

I got the sensor for £68 ($107USD) by quoting the Bosch part no (written on the side of the sensor) to my local autofactor who ordered direct from Bosch.