Engine cutting out and heavy vibration - help please!

[skuzle]

I recently bought a 94 GT. It runs great, but usually under hard acceleration and sometimes just cruising speeds, the engine will cut out. I have replaced plug wires, made sure the battery isn't arcing anywhere, and I still can't find what on earth is causing the problem. Anyone have any ideas?

Secondly, in higher RPM's, the shifter vibrates almost out of control. I'm guessing motor mounts or possibly the balancer. Anyone have any ideas there?\

I would appreciate all the help anyone has to offer. Thank you.

 

[BlownFiveLiter]

The cutting out is probably the TFI, it's a pretty common problem with our cars from what I understand. When the shifter vibrates, is it related to speed, or just RPM? The balancer is the first thing I'd suspect, and it only takes a minute to look and see if any rubber is sticking out anywhere. Looking into whether it's slipped at all is a little more involved, but fairly simple, just needing the number 1 cylinder to be at TDC on the compression stroke, and check to see where the pointer is at on the balancer (if you know where the timing was set). Good luck, and welcome to SN!

 

[skuzle]

I'm new to V-8's because I used to drive a rice burner, and honestly, the mechanical side of cars I know quite well, when it comes to electronics, I'm not so good there. What is a TFI? lol... I've also heard of a lot of people replacing their driveshaft with an alluminum one and that fixing their vibration problem. Yes or no? lol

 

[StangRider1]

skuzle,

The TFI is a module that (I think) tells the distributor when to fire(I'm a little weak on the electronics aspect myself, Someone please correct me if I'm wrong). As Matt said, it's a pretty common problem with our cars, and hard to diagnose if you don't know what to look for. Mine went out several years ago, and it took 3 different shops, and more than $500.00 before I got it fixed. As for your vibration, the balancer is the first place I'd look, if the rubber is showing, I'd find a replacement. If it's not, then start looking at other possible causes, like the driveshaft.

 

[Nagash01WS6]

TFI module is on the passenger firewall below the intake tubing. Its mounted to a aluminium heat sink. You can pop the cover off of it and see if anything appears to be overheated, or make a trip to Autozone or Discount Auto Parts and pick one up for $50.

My car was cutting out through the entire RPM range. Cap / Rotor / Coil / Plugs didnt fix it. Snagged a TFI off the other car and it ran great.

 

[BlownFiveLiter]

Nagash01WS6 got it before I got back here to look. It's your ignition module, and they tend to be fairly problematic. They're fairly cheap to replace, so I'd do it anyway, even if it doesn't fix the problem, since it'll probably fail eventually anyway. Or just keep it in the car in case you break down. Aluminum driveshafts can alleviate the problem of vibrations at speed for some people, but that doesn't necessarily mean it's where the problem lies in your case. If it's vibrating at a stop when you rev the engine, I'd look at the balancer, or that something is out of balance. Hope this helps, I can't offer any more advice for the night, I'm off to work for the next 12 hours

 

[skuzle]

Thanks a lot of the help everyone, I greatly appreciate it!