so today me and my friend were taking a look at the code that was coming up in my 91 formula 305 tpi. i put a wire in the 2 connectors to check out the code and told my buddy to turn the ignition on. instead he goes to start the car and it started making some crazy noises. now it wont start at all and when you go to start it, it sounds similar to a battery going dead but a lot worse. and the battery is still good. I'm guessing the ecm got fried. has this ever happened to anyone before?

 

It happens rarely, but it CAN happen. This is why we are always cautioned against attempting to start the engine with the jumper installed in teh ALDL.

You may be able to correct things by disconnecting the battery for about half an hour. Once the battery is disconnected, turn on the ignition and some load (like the headlights). This will help dissipate any stored power in any of the vehicle electronis, including the ECM.

 

Is he/she still your friend? Or did you beat him/her with your tire iron? Sounds like something a blonde would do! Seriously, sorry for your misfotune. good luck.

 

might have fryed the control module in the distributer

 

yea i disconnected the battery yesterday for about an hour and then tried it and still the same thing. I tried it like 20 times last night. this morning i go to show my dad and it fires right up. i was like what the hell. so apparantly cars do fix themselves haha. so the code that was coming up is code 12 which means that there is no code i guess. but when i start the car and its cold, the check engine light come up and the car backfires like crazy when i floor it. definately sounds like its missing and like it has a really bad vacuum leak. once the car warms up and i shut the car off and restart it. there is no check engine light and the car runs perfect. i changed the ign module, plugs, wires, cap, and rotor and it still does it.

 

1. Don't "floor it" when the engine has not had a chance to warm up. You'll be getting the express ticket to that new engine very soon if you keep doing that.

2. If the "SES" light is on, something is wrong. a '12' means there are no/missing distributor reference pulses. That would be consistent with the misfire and backfire. I'd start checking out the ignition wiring and components. HEI modules, pickup coils/reluctors, and ESC modules can be temperature sensitive. Try bypassing the EST and starting to see if the backfire persists.

3. Disconnect the battery again for about a half hour or more to clear the BLM tables.

 

haha thanks for the help. even if i wait for it to warm up after a cold start, it still backfires until i shut it off and then restart it. then it runs perfect. if i blow the 305, that will just give me more motivation to build a 383 stroker. but thanks again

 

WHAT? code 12 is entering diagnostic memory mode. You will always get that before and after the trouble codes because the engine isn't running. Check the codes again for something other than 12. If the SES light is coming on at any time your ECM should register a trouble code other than 12. Unless it's fried.

 

ok so i finally got a code out of her. its code 42. doesn't code 42 usually refer to an ignition module is bad or something. I just put a new one in about the same time my car starting ascting like this. I put an accel ign module i bought for my old 89 formula 350. isnt it the same ign module thats in a 305 tpi and 350 tpi???

 

Yup, 42 is ign. module, short in circuit, poor elec. connection, or bad ECM. If you have the EST ignition system, first check the connector in the wiring harness (black plastic), that runs across the firewall from about the center of the car to the passenger side. and make sure it's together good. Being the 305 & the 350 stroke is the same I think the modules are the same but don't hold me to it! Best way to find out is call the parts store and ask them to look it up and see if there's a difference between them. You can also take your ignition module in to Auto Zone and they will check it for free! I had mine checked there and they said it was fried. Bought a new one and it fired right up. Mine quit on me while driving 55 and put me straight on the shoulder of the road. I had to get it towed home on a rollback
because it never hit a lick till I replaced the module. Getting the cap off isn't much of a problem but getting it back on straight is a PITA.

 

Yea this weekend i'll pull the ign module and have it tested. The reason i had the extra ign module was because i bought an accel for my old 89 formula. i put it on and the car ran like ****. i couldnt figure out the problem. it ended up being the ign module that was only a week old. so i wrote a letter complaining to accel and they sent me a new one for free. i guess they musta gave me a crappy one too

 

yep just got the ignition module tested and it is bad. Kinda sucks considering the ign module has only been in my car for like a week. anyone else had problems with accels ign modules?

 

The only Accel part's I've ever used are the spark plug wires and high voltage coils. Everything else I use GM only.

 

so today i just bought a new ign module. put it in my car and now my car wont start. its doing what i described in my first post. making that really weird noise. the car doesnt crank over, it kinda sounds like the battery is going dead but a lot worse. maybe its my coil or possibly my ecm.

 

Might want to pull the panel on the pass. side under-dash and drop the comp. and check all the wires and grounds. See if one is cooked. Strange though, it would start with the bad Accel part and not with the new one.

 

yea these TPI electrical components are starting to **** me off

 

Technically, a '12' is for missing distributor reference pulses. Since you'll always generate that condition when the engine is not running but the ignition is on, it will always display. I think you're confusing the '12' with an '11' in the old Ford EEC systems. There are times when the '12' can actually be an error condition if the HEI switching module does not send expected reference pulses to the ECM during a run.

As for the '42' you generated, that will be normal if you disconnected the EST bypass connector to check/set the base timing.

Have you tested the ignition coil yet?

 

1979_transam
Do you have a meter? There are some simple checks you do if you have one. Did you get another Accell coil? Do you have any junkyards near you?

 

got it running last night. it was a combo of a bad battery/ign module/and coil. thanks for all the advice

 

So, did you get the module checked again? Check the coil? Charge the battery? Just buy all new stuff and got lucky? What?
Man, you can't just leave us hang'in !!!
It's like reading a whole novel only to find the last page is torn out!!

 

 

haha sorry guys. I didnt test the ignition module again. I bought one from autozone with a lifetime warranty which was suprising since usually electronic components dont have any type of warranty. So i tried to start the car with just the new ign module and no luck. It definately sounded like an ignition problem. On my old 89 Formula, i remember the coil going out and it took me like 5 weeks to figure out what it was. because sometimes it would start and most of the time it wouldnt. it ended up being a weak coil. so for my 91 formula i figured why not just buy a msd coil. so i did put it in and the car still didnt start but the crazy loud noise went away. the noise now just sounded like a dead battery. it actually tried to crank for a sec. so i swapped batteries with my 79 trans am and the formula started right up with no check engine light or anything. knowing my luck, in about a week something else will break on my formula and i'll keep you guys posted. I have the worst luck with TPI's.

 

so i actually sold my formula today. after all this trouble i went through, i finally get it fixed and i sell it. eh i made $600 off of it. pretty good for only having the car for 2 months

 

The ONLY reason WHY you would do that is to put more money into the 79 RIGHT?

 

haha of course. I might be selling the 79 if i get a rediculous offer for it. if not, i'm just gonna slowly restore it. I wanna put a built pontiac 400 or 455 in it within the year. plus i wanna buy a 99 LS1 Trans Am Medium Blue Metallic too. I almost bought one last year, biggest mistake of my life. haha heres a pic of the 99 TA i almost bought.