Hello everyone,

I'm having a problem with my car jerking when driving, mainly from 50mph - 60mph and it can start right around when the turbo gauge is halfway and starting to climb into the white part. I'm unsure though if thats the only time it does it. Heres what I did to try and improve the problem. First I thought maybe the caytyst was clogged. When tapping it I noticed it sounded solid. So all I could do was drill two holes on each side of the muffler before the caytyst converter to release the pressure. It helped somewhat, next I test the throttle postiton sensor which read 2volts at idle and climbed to around 4 or 5volts when idled high. So I think its working fine. I don't get these jerks when the throttle position sensor is unplugged but it really dosen't mean that could be the problem because as I stated it seems to read correctly. When these jerks happen I lose power and it happens in sperts when I need power to get up a hill or pass someone. In town it runs normal. Its really a tough problem to solve. I wondered if the mass air flow sensor could make this happen?? When driving the car and the jerks start to happen, the motor still runs fine and it dosen't miss fire because my RPM's stay steady. It does it in 3 and 4 gears and overdive so basically any gear when up to 50 - 60 mph. I think it might even do it at other speeds too. So I just thought I'd see what some people thought about it before I shovel out money to test it at a garage, thanks.

P.S It just seems like I don't have enough power when I kick it in and get on the gas, often the motor will work hard and the car catch up and go, Almost like something is wrong with the turbo. It feels like something is clogged or its getting bogged down by something, I replaced the fuel pump, fuel filter, spark plugs, and fuel pressure regulator and the spark coil is also working correctly. No vacuum line are unplugged. Everything looks fine I really don't think its the motor or tranny. I myself am leaning more toward a sensor or the turbo going bad in it.

 

"So all I could do was drill two holes on each side of the muffler before the caytyst converter to release the pressure."

How big are the holes ??
There is the engine, the turbo, the "cat" and then the muffler. I'm guessing you drilled between the turbo and the cat as drilling at the muffler is after the cat and wouldn't really release any pressure ??

Do you have a check engine light on ??

 

I would say they are 1/2 inch holes, pretty sure on it. The car sounds somewhat louder but not really that noticeable. I've had turbo's can go bad alot. And this ones 20 years old or so. To be honest, thats one area I haven't been in and don't know how if you can inspect the turbo by taking it apart.

 

Easy thing to do is take off the intake tube from the air filter to the turbo and gently put your finger in the intake side and see if it can easily be spun. If it binds at all it needs to be rebuilt.

 

Thanks I'll give it a try later on, its hot outside right now. When I drive around town I do notice a slight spurter when applying throttle. It seems like something is clogged and not allowing power to be delivered in certain situations. But then again it has power other times which makes me scratch my head. I replaced the spark plugs but it still has the original spark wires and distributor. I just don't know if the problem could be caused by the car missing. It never and this jerking problem until about a month ago, before then everything ran fine, and it seems the motor is running just the same as it did before this started.

 

Didn't see distributor cap, rotor, and plug wire set on your list. Recommend OEM for all these items.

This sure sounds like ignition secondary break-down to me. I would replace those items first (sounds like they're due anyway) and go from there.

And like kfrog said, do you have a CEL on? The OBD1 codes may give you clues.

 

If you haven't done them or don't know when they were last done that cap, rotor and wires would be a good idea to take care of now. You eliminate them as a possible problem and might even cure yours !!

Wouldn't hurt to pull the plugs and make sure they were (are) gaped correctly.

 

The spark plugs were all firing but I got new ones anyway. I will try and save up to replace the distibutor, probably the rotor will be replaced first. And then go from there and replace the spark wires.

When I put the car into drive and hold my foot on the brake, it idles and every now and then it will sound like its missing. For a split second I can hear it cut out, then go back up. Driving in town I can hear it cut out too. Sometimes even feel a little hesitation. Now with it doing this, Imagine what it could do when going 50 or 60 and I need some extra power to climb a hill. Maybe the problem of it missing is being magnified and in turn causing the rough jerking. Its one theory I have among many lol. Either that or its a sensor messing up and causing the car to run poorly. Idk