x type 2.0 ltr petrol; 2003 81000 miles
car motoring perfectly at high speed for 450 miles when suddenly lost revs, proceeded at 30 mph until rest stop waited 30 min. all ok again for20 minutes when engine went into limp home.Had plugs/caps relaced. after repair on return trip all ok for 250 miles when engine warning light came on. reduced revs to2500 and motored for further 200 miles until long steep hill, when engine went limp home. waited 2 hours and drove home 2500 rev for 140 miles. All O.K. now but light still on. colin. France

 

Step one, either read the codes or have them read. An OBDII code reader is not very expensive but invaluable to have. Here in the US most of the parts stores will read them for you for free in hopes of selling you the needed parts.

Once you have the codes, come back here, click the search this forum button, enter the code in the search box. It will return what is causing the problem and more often than not, how to fix it.

 

Colin, first off, welcome to the Forums. Lots of good information here and even better people. We do ask that you stop by the New Member section and give us a quick intro about you and your car. We pride ourselves in being a better car group, and as part of it, we like to get to know one another. This will also give you a chance to meet those that make this place what it is.

As for your problem, it could be a lot of things. The best advice that I can tell you is to get the codes read from the plug under the dash. You should get a code like "PXXXX" where XXXX is 4 numbers (for example, P0171). This will help us a lot in giving you specific information to fix the problem with the first part, not on the 5th one. From the sounds of things, you have a minor vacuum leak that is giving you grief. Based on the age of your car, I would be looking at the line between the engine and the brake booster and the PCV hose (between the PCV valve and the intake). I know with the 2.5L and 3.0L motors, the common problems were the brake booster line, PCV hose, and the IMT valves. Looking at pics on the internet, the IMT valves are the 10CM black circles on the top of the engine (there is a single o-ring under the cover), the PCV hose is the one running from the front valve cover to the joint just downstream of the throttlebody, and finally the hose from the joint downstream of the throttlebody to the brake booster.

Let us know what code(s) you get from the reader and go from there. If you want to get your own code reader, you can get yourself an "ELM327 V1.8" device (can be found on e-bay for example). YOu just need an Android phone to be the screen for the ELM unit. It will have an app added called "Torque". The ELM unit will cost you $20 USD (or less) and the app is free. As a side note, you DO NOT!!!! want the V2.1 ELM327 unit. This is meant for the newer version of the OBD computer system and does not work well with your year car.

 

hi, bud and "Thermo."
Thank you very much for your quick answer. I had a code reader on order, Autel AL 319. It arrived today and the codes were P0420 & P 0430 and pending P1000. I have already changed Air filter and today had an oil change, during which the mechanic checked the whole exhaust system and reported that all looked OK without any leaks. Car still working without any problems idle speed rock steady at 900 ish. I will check the hoses as suggested and also clean the MAF sensor. Should I clean /change the oxygen sensors.. I don't believe its the cat converter as it has only been in for 12000 miles. Once again thank you for kind advice
Colin

 

Smiffy, I would not worry about cleaning the O2 sensors. Because you have both P0420 and P0430, that would be showing me that you have a minor vacuum leak somewhere and that is causing your car to run lean. These codes are really for a low efficiency on the catalytic converters which normally means you have a bad O2 sensor on each side of the engine. But, what are the odds that you have 2 (or more) sensors that all failed at the same time. Pretty unlikely. So, you have to take a step back and look at what else can cause these symptoms.

With that being said, I would also check fuses F38 and F42 in the engine bay fuse box. It is possible that the heaters have failed and that is causing your errors which a single fuse would affect an O2 sensor on each header. After that, I would be looking at the PCV tubing followed with the accordian tubing by the throttlebody. Whatever the problem is, it has to affect both sides of the engine.