304 missfiring

[skippy73]

I have a vt 304 which is Miss firing While Accelerating an surging when sitting at speed.
When it first started I replaced spark plugs with a one mil gap sparkplug leads, then the alternator cable burnt out replaced the cable. Then noticed the distributor was burnt out in one of the plug holes. replaced the distributor cap replace the rotor button Check the timing in diagnostic mode set a 10°and it still has a miss the only code that’s coming up now is 22 TPS sensor Have a check for vacuum leaks can’t find any, checking the wiring for tps now.. . Anyone have any thoughts

 

[BlackVXGTS]

Replace your TPS.

 

[skippy73]

No Not yet, So you’re thinking That could be it

 

[Forcedvp]

No Not yet, So you’re thinking That could be it

Sounds more sinister than a TPS. Usual suspect for these motors is Coil(will not throw a fault code if faulty) and Ignition Module(same thing,won't throw a fault code). Other possible cause could be Dizzy and or Hall Effect Sensor. One thing I would do first, is eliminate the possibility of water in your fuel tank. Fill tank half way and put 1L of Methylated Spirits in tank and drive for about 15-20ks. I have had this problem before with my 304 VT. I replaced everything( leads, plugs, coil, dizzy, module, ect) and still had miss fire. Then i remembered what my father did with his car. I put a bottle of spirits in the tank. 2 drives later the miss fire was gone for good! I would try that first.

 

[skippy73]

Okay I have replaced the coil An the TPS sensor an calibrated it, but still got the missfire. Heading down to the shop now to buy some metho

 

[whiskeytango]

Clean your MAF sensor while you're at it.

 

[Not_An_Abba_Fan]

Usually bad leads cause that, but if you have replaced them check that they are all seated correctly on the plugs and the cap. I'd check the cap, it's a bit of a prick to get it to seat correctly, if you have adjusted the timing you may have dislodged the cap and it's not sitting square on the dizzy. Another thing that can happen is that the little locating lug on the cap rounds the corners off if you try and turn the dizzy by the cap and it will throw the timing out, but it won't usually cause a miss.

 

[skippy73]

Okay so I’m now sitting on the side of the road car died fault code 31 coming up. Theft deter ant no signal, flashing red light on the dash very very faint. Car locks via the key but wen u try to start it just clicks like it’s the solenoid but replaced It yesterday.

 

[Forcedvp]

Okay so I’m now sitting on the side of the road car died fault code 31 coming up. Theft deter ant no signal, flashing red light on the dash very very faint. Car locks via the key but wen u try to start it just clicks like it’s the solenoid but replaced It yesterday.

Sorry to hear that. You're having rotten luck. Check your relays (ignition relay i think is in the engine bay fuse box) swap it with a headlight relay and try to start it. I think the ignition relay is the blue one. Do you have an aftermarket immobiliser fitted?

 

[whiskeytango]

Is the actual key loose. Like the contacts that turn on the metal strip? Happened to me before.