No Power

[Visions]

89 535,,,, 150k miles

Hello,,, a friend of mine bought this car and ever since it hasn't had any power... You can stomp on it and it will gradually get up to speed... Car idles a bit rough but revs up fine and seames to have power until you put it into gear... Trans shift very smooth... Has new fuel filter,,, not a fuel pump problem because I put mine in his car just to test that out...

Took the car to a shop that only works on BMW's and they said they got some fault codes and some codes they didn't know what they were and one code said the Computer wasn't working properly... I put my computer in his and still had the same problem... One code they pulled up was Torque converter and it even showed up on the screen but ever since I traded out computers it hasn't showed up again... could of just been the damn comp giving out wrong codes... Anyway I just don't trust them cause all they did was read codes and tell me I needed another TC and Trans... but the trans shifts like a dream... Just afraid they will trade that out and it wont be the true problem...

My regular mechanic has gone AWAL and doesn't answer his phone anymore,, going through a divorse and who know what...

Again the car drives fine but just no power... shifts fine,,, if you were used to driving a geo metro you wouldn't even know there was anything wrong but I know that car should have alot of power... Hell my 735i kick *** and his should be faster...

What do you guys think...

[DaveVoorhis]

As a starting point, search for the "stomp test" to obtain the codes from the ECM.

I'd also look at obvious maintenance items first, such as the air filter, plugs (read them before you replace them), distributor cap and rotor, plug wires, oxygen sensor (if you've got one), possible leaky air/vacuum hoses, restrictions in the intake and/or exhaust, valve adjustment, etc. Also, verify that full throttle opens the throttle body all the way, and that the kick-down is working. Carpet jammed under the pedal can make a fast car go very slowly.

Engines are pretty simple devices. Given proper compression, valve timing and opening, ignition, mix of air and fuel, and unrestricted exhaust, they produce power. If an engine is operating within design specifications, accessories and mechanisms attached to the engine can drag and reduce power, usually converting it to heat and/or noise. Check for transmission problems, seized A/C compressor (usually the belt won't last long), dragging brakes, etc.

[Cor-Man]

My car was doing the exact same thing, but my car has EML (drive by wire throttle). I even had the torque converter lockup code. It was going into "limp" mode because my warning lite in my instrument cluster for the EML system wasn't working. Any problem with the EML system will initiate the "limp" mode. The car will rev to red line or close to but really slowly at wot. Being your car is an 89 I dont think it will have EML but I'm not sure.

[Visions]

I just checked Shogun's site on EML and BMW didn't make them for the E34 until 1991...

Thanks

My car was doing the exact same thing, but my car has EML (drive by wire throttle). I even had the torque converter lockup code. It was going into "limp" mode because my warning lite in my instrument cluster for the EML system wasn't working. Any problem with the EML system will initiate the "limp" mode. The car will rev to red line or close to but really slowly at wot. Being your car is an 89 I dont think it will have EML but I'm not sure.

[Alexlind123]

Parking brake on?

[Visions]

Parking brake on?

No,,, but I thought of that and made sure it was disengaging... That would make it quickly slowdown but the car coasts as usual...

I'm no mechanic but I will change out the plugs, distributor and rotor to start and go from there... Also will check for vacum leaks... Will checkout the throttle body but right at this moment I don't know how to check that... I have read about the Throttle body but havn't read how to clean it up and make sure it is working properly... Been reading for hours today on anything possible

[Jay 535i]

No,,, but I thought of that and made sure it was disengaging... That would make it quickly slowdown but the car coasts as usual...

If the parking brake is on, it won't take long at all for enough heat to build up to demolish the parking brake's decelerative ability. You say the car coasts fine. I don't think that's a good test. A better test would be to see if it will roll down a very gentle slope of its own accord, like a driveway, when the brakes are cold.

I doubt the parking brake is your problem, but I thought this was worth mentioning. More than once, I've seen someone claim that the problem couldn't be the brakes because the car coasts fine, only to discover that the car coasts fine because the brakes are at 2000 degrees.

In fact, when my car was my father's, he had this problem. He drove around for a week with a seized front caliper. Since the problem 'disappeared' after a couple of miles he wrote it off as no big deal. What was happening was that, after a couple of miles, that brake had overheated so badly that it was no longer creating any friction. If he'd just touched or smelled around the wheel after a trip he'd have figured that out.

My father wasn't the brightest chap, but I owe my love of cars to him. R.I.P.

[DaveVoorhis]

Will checkout the throttle body but right at this moment I don't know how to check that... I have read about the Throttle body but havn't read how to clean it up and make sure it is working properly... Been reading for hours today on anything possible

Take off the pipe from the air filter box to the throttle body. Peer down the throttle body, and open the butterfly. Is everything coated in oil and gunge? If so, take off the TB and clean it in oxygen-sensor-safe carburetor or throttle body cleaner. Re-install and start the engine. Spray more oxy-sensor-safe cleaner down the throttle body to clean gunge out of the intake manifold.

[Visions]

Take off the pipe from the air filter box to the throttle body. Peer down the throttle body, and open the butterfly. Is everything coated in oil and gunge? If so, take off the TB and clean it in oxygen-sensor-safe carburetor or throttle body cleaner. Re-install and start the engine. Spray more oxy-sensor-safe cleaner down the throttle body to clean gunge out of the intake manifold.

Thanks I easily understand that and I bought some throttle body cleaner today... That was a big help


Is it possible that the TPS isn't working and it doesn't sence more throttle?... Looking from the left side of the engine bay is the TPS on the right side of the intake manifold?

[Visions]

If the parking brake is on, it won't take long at all for enough heat to build up to demolish the parking brake's decelerative ability. You say the car coasts fine. I don't think that's a good test. A better test would be to see if it will roll down a very gentle slope of its own accord, like a driveway, when the brakes are cold.

I doubt the parking brake is your problem, but I thought this was worth mentioning. More than once, I've seen someone claim that the problem couldn't be the brakes because the car coasts fine, only to discover that the car coasts fine because the brakes are at 2000 degrees.

In fact, when my car was my father's, he had this problem. He drove around for a week with a seized front caliper. Since the problem 'disappeared' after a couple of miles he wrote it off as no big deal. What was happening was that, after a couple of miles, that brake had overheated so badly that it was no longer creating any friction. If he'd just touched or smelled around the wheel after a trip he'd have figured that out.

My father wasn't the brightest chap, but I owe my love of cars to him. R.I.P.

Its not the parking brake for sure... Just this past month it got new brakes and rotors... calibers were fine... My 735i on the other hand just had a caliber lockup so I know what you are talking about... thanks