1994 Volvo 850 Q&A
1994 Volvo 850 Question: Garage can't get my Volvo 850 out of limp home mode.
My car has been going backwards and forward to the garage for weeks as it needed a new mass air flow meter. That has been changed but the garage can't get the car out of limp home mode which as I have to have it back for work three days a week. It's costing me a fortune in petrol but I can't afford to take it to a Volvo dealer. From what I have found out so far, it looks like once they have fixed the problem it should clear the codes and be ok, but they just can't get it out of limp home mode. I'd be very grateful if anyone has an answer for this. - alice2
This vehicle has a limp home mode for the transmission, which will cause it to start in 3rd gear, but the engine management system will not go into a limp home mode. I would have all the codes checked, recorded, then erased. Drive the vehicle and recheck the codes. Post the codes here and I can give you further info, but I need to know what codes are being set in the engine and transmission modules at this time. Also, do you have an automatic trans? Turbo? - Bret Bodas
Hi Alice2, I am a former Volvo tech, had about 25 years in the dealer and I might be able to help you. First of all even the European cars are all fuel njected, for this year model, none of them had carburators. What they have is an air mass meter and a throttle body. The big deal is whether or not this is a Turbo first of all. If the turbo charger has gone bad, or if the vacuum actuator for the turbo is siezed up it will kill the power in the engine and you will feel like you have an anchor behind the car. Second if you have a stick car then I doubt it has a turbo charger as Volvo didn't like to put Turbo's on straight stick trans cars. There were some other issues with these cars. They have a metal fuel filter under the car on most models that has a paper type filter material inside it. I have seen these where the paper inside collapses on the older models and blocks the flow of fuel. So have them check the fuel flow and the fuel pressure at the injector rail, it should be around 30 psi. The last thing has to do with the fuel pressure regulator. I have seen these go back and what happens is the diaphragm inside collapses and will block the excess fuel pressure from returning to the tank causing a very rich fuel mixture and flooding the engine. One other thing is a must and that is to look at the ignition coil. Volvo had a problem with the coil arcing to the metal frame around the coil and when the engine starts to get up to speed the coil arc's causing loss of power to the spark plugs and missfires. This is evident by white around both sides of the coil on the metal frame by the coil windings. I know this is a lot of technical mumbo jumbo but take it to the shop you have looking at it and tell them to check out these things. Also know that clearing the codes should clear any limp home mode. Make sure if you disconnect the battery to get the radio code to reset it from the dealer if you do not have it. You only have 3 chances to put it in or the radio will be locked out. Thats another story. I hope this helps, have them check the timing belt also to make sure the car is in time. Good luck. - johnnyk17
ya i bought a new mass air flow sencer from NAPA . still had the same proublem you have , brork down went to the dealer, he put a Volvo mass air flow sencer in its bin fine for last 3 years . the dears part was less than the bad one i got from NAPA. they only $40.00 labor ,loluck 2x 850 owners - Visitor