Guys,
I just bought a 2000 S40 for my daughter yesterday. We made this buy because we just bought a XC90 2006 and feel in love with Volvos!
The problems I am having with the 2000 S40 are very bad. It drove off the lot fine, but about 15 minutes later, could barely pull its own weight down the road. Very week on power and I had gas pedal to the floor. Almost like it was tied to a big truck pulling down the road! Very week!
The trans seemed to be fine, and it runs like a top, other than when it starts this problem. After we stopped and it cooled down, it started driving fine again.
More info on the car:
Millage 180,000 (no record of any service available),Check engine light on, All fluids are correct, codes are P0336 (camshaft pos. sensor)and P0341..... Pending codes P0335B and P0341.
I did notice that when it was running week, that the exhaust pipe behind the engine and against firewall (after the turbo area) was cherry red hot!
Could these problems be Cat.Converter? What would be my first thing to look into? Any ideas on the power problem? Also may be a combination of a few problems, but I am not sure.....Thanks in advance guys and Im glad to be a new member and look forward to being on the site.

 

More info......I took it down the road today, and it started right off with my problem.....gas pedal to the floor, to even get it to move,and very low power. I pulled over and started and re-started the car about 3-4 times...crank it up, and off it went...running pretty good till parked. ..HELP GUYS! Im lost on this one!

 

I've had a clogged cat converter cause no power issues but that was on an old old car. The quick test is to physically remove the upper O2 sensor and run the car to see if you pick up some lost power. Don't run it like this for long as hot exhaust gases are entering the engine bay.

I would also check the fuel pressure. A glowing exhaust indicates a very lean condition. Might even consider replacing the fuel filter since you don't know the history of the car.

Have you erased the trouble codes to see if they return?

 

Thanks Hudini,
No, I have not removed codes yet...I will get it back to the guy with the computer and have hime do this (or is something I can do with out the computer). Forgive my lack of knowledge on this car, I dont have the best mechanical skills.
It does seem to be an "off and on" again problem...sometimes it drives off fine, then sometimes it cant pull its own weight. I also notice that when it does its worst problem of barely moving, that I have smoke coming out the back exhaust...greyish in color???
I have also been adviced that the codes may be a speed sensor (which makes since, because the speed odm. needle is not working). Can this pay into the other problems?

 

I've only erased stored codes with an OBD-II scanner. You can pick up a decent scanner at Harbor Freight for fairly cheap. Places like Autozone will also scan for free but they won't erase the codes. If you scan the car yourself you can erase them easy enough.

The "on and off" again makes me think electrical. Does the speedo work when the car runs well? Also, can you smell the exhaust when it is running poorly? Car smoke tends to be blue = oil, black = too much fuel, white = steam (water/coolant). The white smoke tends to smell like anti-freeze, that sickly sweet smell. Gray = ?

Have you removed the spark plugs and checked the color? Plugs can tell you many things. Black dry sooty = rich, black oily = oil fouled, light brown = good, and bright white = steam cleaned from a coolant leak (assuming old plugs). Also if one plug is different than the others can point you to the problem.

 

Thanks Hudini,
Great info, and thanks for the time to answer my questions.......
It was a greyish color smoke, but only did this when it was running in the bad stage of action..maybe it is fuel related or a combo of some other things?.....I did a few things today, I cleaned the throttle body (it was very dirty), and used MAF cleaner and cleaned the sensor there as well. Also the cat.coverter has been changed and is now no longer in the equation. All this being said, it did seem to run a little better, but not what I would think is right yet...although, I have not had the "stall in power/pedal to the floor" happen yet (it comes and goes).
I went back, and had the codes erased, and it threw the crankshaft position seensor(P0336) code again...and camshaft positon sensor pending.
The speedo doesnt work at anytime at all, but everything else is fine, including digital readings. The ABS light is on as well on the dash display.
Next step, I guess, would be to replace the Crankshaft Sensor and also check all the plugs...Does this seem to be my best next step, Hudini?...Thanks again

 

Assuming you don't have any loose connections on the CPS harness then yes, to me, the next logical step would be to replace the crank position sensor. The car may be in "limp home" mode. I'm wondering how it runs at all with that problem. The ECM needs the crank signal to fire the plugs unless the limp home mode has an alternate method like the cam sensor.

The ABS light could be simply a wheel sensor bad or could be worse (i.e. expensive) with the ABS control unit bad. I've not had issues with mine so I'm not any help there.

 

Ordered the Crankshaft Postion Sensor today...I hope this will be the problem. I am loving this site and the good info...thanks Hudini

 

More info and where I am today:
I bought and changed out the Crankshaft Pos.Sensor and also istalled new plugs. The problem actually got worse....I was however able to catch the car in the act on the computer, at a friends home.

Codes now say:
P0341- Camshaft Pos A Circut range PERF Bank!
P0335B- Crankshaft Pos. Sensor AA Circut Malfunction
P0101- MAF Sensor
P0351- Ignition Coil A Primary-Secondary Circut Malfunction
P0300B- Random Multipal Misfire

Quite a list, especially since i just put in a new Crankshaft Pos. Sensor??It also will not act right after a few restart, now its just straight out mis-behaving!
......Any thoughts guys?? Thanks in advance for any info

 

Well, I found the two misfiring coils....I will change them and see what happens. Man! This thing is giving me a fit! All the coils where firing before I changed the Crankshaft Sensor!!....eeeekkkk!

 

Have you ever found out the problem? I am having very simular problems.

 

Hey, No...as of right now, there is nothing new. In fact, I quite driving the car, and decided that trying to sell it not running right would be a bad idea as well. I have thought about trying a new ECM Mod in the car, and see if that fixes it. If it does, I will put it on here for everyone to see.
Sorry you are having the same problem...its hard to get a fix for this one.