I have an 87 TN fuel injected that runs perfect in neutral and reverse but as soon as you put it in drive it runs like its only firing on two cylinders once you get moving it smooths out a bit but still misfires. I own two other Magna's and have owned plenty before these and never had this problem before has anyone else had this problem or can help? Cheers Exis

Checked all the electrics like plugs/leads/distributer?

Checked all the electrics like plugs/leads/distributer?


Done that changed plugs leads dizzy cap and coil seen a few mechanics but they want to experiment which each one will cost$ they haven't come across this problem either

Sounds like it could be the TCU.

Pull it out open it up. Smell it and check for capacitor fluid.

Search TCU threads if you like. Alot pop up in the 2nd gen section.

Sounds close to my miss fire problm last month. Do a seach in here or the 1st gen section.
Everyoe told me that it was the tcu and that i should try another in it's place. but the thing with the tcu is it iether works or doesn't. so seeing as your car is running id say thats not it.
So anyway before trying another one i put a new dissy in there and presto missfire gone:D

If it was the dizzy that was at fault wouldn;t it misfire all the time and not just in Drive?

If it was the dizzy that was at fault wouldn;t it misfire all the time and not just in Drive?

depends. if the plug was playing up maybe not. Cos alot of the time they become lose and as your engine vibrates moves it might be fine then. for example it changes gear which moves the engine and in turn moves the plug so it's not contacting properly again thus making it miss fire. mine got to the stage that some days it would be fine then other days it was really noticeable. plus the time of day made a difference as well. in the morning when it was cooler it would play up more than midday when it was warmer.

so really what i was getting at is id take alook at the dizzy first before the tcu seeing as they seem to be a common thing to play up.
Also id clean all the connections in tha engine bay with crc co contact cleaner first (with paying more attention to the dizzy plug) before doing anythin else. it the cheapest option and it might just be a little corrosion in the dizzy plug thats giveing the miss fire.
also i was just giving some more food for thought just incase the tcu was found to be fine.

how olds your coil?

I transfered all the electrics off my other magna leads coil plugs dizzy cap didn't make a difference I will look at the tcu tomorrow:nuts:

I transfered all the electrics off my other magna leads coil plugs dizzy cap didn't make a difference I will look at the tcu tomorrow:nuts:

yea but did u swap the dizzy as well not just the plugs leads and cap?? if no then you haven't ruled it out. but if you have a parts car then you might as well swap it and if no change then swap over the tcu. have you cleaned the dizzy plug?? cos before i had a miss fire problem i had a starting problem. couldn't get it to start and was advised to clean out the dizzy plug with crc co cleaner. after cleaning it started first go. plus with the age of the car it wouldn't hurt to spend 12 bucks on can and clean all the connections in your engine bay. after doing this to my tp it ran smoother .I highly recomend it.

the wiring loom connections that plugs into the dissy and contacts corrode and loose contact during vibration or load

go to the wrecker and get a new plug and replace it solder in and insulate

same with the 0 rings on the injectors and fuel pressure regulator

check for broken wires on the sensor wires and check the air flow meter and tps functions

the wiring loom connections that plugs into the dissy and contacts corrode and loose contact during vibration or load

after cleaning out all my wiring connectors, I placed a small nylon cable tie around each to stop them possibly vibrating loose. Do not over tighten the cable ties.

I would also suggest starting the motor in total darkness, pull hand brake on very tight with bricks infront of wheels, place in drive, open the bonnet and standing to the side of car slightly (very slightly) increase revs by hand and watch for any arcing/sparking from leads-plugs-dizzy etc while under load.

check your plugs

so any luck with the miss fire?? did you swap the dizzy and or tcu??