Need help 81 GTSI Ignition problems

Been a while since I last played with it (2 years now) got around to checking resistance on my TDC sensors 704 on two and 750 on the aft most one, my electronics training tells me this isn't enough to be concerned about but I thought I would ask the experts here before going on to ringing out the rest of the harness checking all the wiring.



History
Lost a bank and cat is loading up to a point of a cat fire

Had found a sensor shorted out before and fixed it then car was running great let it sit and now it is doing same thing all over again.

Any way before trying to start it again I want too check every thing out all over again.

Thanks in advance for any help

 

I don't know which is the 'aft' sensor...but know that 2 are for tdc timing function whereas the third one is for tachometer engine speed functions and could easily have different characteristics.

Have you tried reversing things, like the coils or plugs at the ECU units, and note if the problem follows along (changes bank)?


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http://www.ferrari308gtbi.com/

 

Hi Paul thanks for the replies
Yes I have tried many things, I want to eliminate many things with the multi meter first this time before trying old fashioned trouble shooting. I don't want a Cat fire again.

Problem should be able to be found with a Multimeter

 

By the way I have checked my manual and that aft most sensor is the Tach pick up not a TDC sensor so that may explain the difference in resistance.

So I think I have eliminated my sensors and should proceed to coils I have no idea what resistance should be does any one else?

After that it will be ringing out all the wiring connections.

I have a spare computer still but I don't want to go throwing that at it till I have eliminated every thing else.-------------------------------------------------------------------
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I am working from a copy of the "Modial 8" "Modail Quattrovalve" Ferrari manual section D! fig.1 for a schematic which does not give me all the wire colors to trace from.

Does any one have schematics of this system for an 81 308GTSI that they can post or email to me???????

 

any one?

 

I don't have a diagram and I'm not aware of one being avaliable anywhere .......

I do have the 328 wiring diagram and a 308QV diagram , , if you want those I will send them.

If you are doing a "new" wiring diagram please do it in color , , , I've always found black and white diagrams with little letters everywhere to match a table more than a bit nuts.

 

Well I checked resistance on coils today and got 6 something top and bottom on front coil rear coil was nothing on top and 6 something across the bottom HMMMMM.


Tried switching wires on rear coil from the top too the bottom and tried starting car for first time in two years with the old gas bad I know but I said what the heck....
The car ran all though sluggish ran by itself too 2000 rpm then after a while dropped too 1000 rpm yellow lt extinguished then tried to accelerate engine a few times seemed sluggish and cylinder 1-4 red light was on intermittently. strong smell of fuel also.

Shut her down ran it up lift checked temp sensor to Cats one of them too the aft bank of cylinders had a spring around one of the wires and was out of whack so I straightened that out a little. Then for ****s and giggles tried switching the wires on the rear coil back too top row and started it again, engine is running on all 8 cylinders but is sluggish still in my opinion.
It does accelerate but kinda slow, and the Cylinder 1-4 light is out all together. no smell of fuel this time around.


Oh well it runs
And now its time to sell

Car has suffered from a minor Cat fire all new replacement parts have been purchased and go with the car.

Car has had new timing belts and fuel pump does have all new tail lights and a new rear bumper and new bonnet cover and a bunch of other stuff!
I am not going to try to get top dollar for it but Its not going to be given away either.
Either way it will be a better deal than eBay that's for sure.

All and all I don't know if I fixed any thing other than just disconnecting a few connectors and plugging them back in I still don't know if it should run like it is or not either. I am used to American stuff!!!!!!!!!!!!!

like I said I don't think the engine is accelerating as it should but it does run now I think I am just going to paint the rear end and sell it as is and cut my losses.

If any one is seriously interested I can be reached at 775 727 1964 house and 775 513 8814 cell I have all the parts to complete and the car must go asap it has less than 10000 miles total. please don't ask for a bunch of photos for your collections as a real serious buyer will come and look besides that I don't think I would sell too any one that didn't come look at it first .

 

I would love to have a copy of yours my email is [email protected]
If they will mach my car????

I have no plane on trying to make one, that for me would entail totally dismantling mine, Yes I too don't like most wiring diagrams Aircraft wiring diagrams are much easier to read and NO stupid colors to follow just numbers printed every six inches or so.

I would like to find out if every thing is right I think maybe that one coil is bad or is going bad.

I need to sell my car now that it runs again unfortunately but I got to do what is best for family. Keeping a roof over every ones head is much more important.

 

OH ya I wanted to say wow has this place changed in the past few years.

I wanted to thank every one that has helped me.



Thank you!

 

Come on now, do I have to post this myself? http://www.ferrari308gtbi.com/

 

Absolutely excellent ! .......... thank you soooooo much !

 

Thank you Paul
I will have to order one

Update I have the car running now and appears to be running on all 8 cylinders been so long since I had it running I forgot what it sounded like.

Any way it does run again and no slow down lights are on BUT engine seams lazy and seams slow to accell any one have any ideas?

 

any one have any ideas?

Could it be that the coil is bad or should I be looking at somthing else????

 

......... I guess you have already checked the real simple stuff .......like is the air filter clean? ...... are the spark plugs new or bead blasted clean ? ...... is the fuel tank breather clear ?

It probably isn't this stuff but it could be worth checking.


BTW , there is 2 suppliers with TDC sensors on e-bay at the moment ... one for $95 and one for $65 ....... I searched "ferrari" and "sensor" and they appeared straight away.

 

Cool I will check those sensors out on Ebay

What do you think about maybe one of the Cat's are bad?
Partially plugged up as it was overheated by the Cat fire couldn't that cause the engine to seam lazy?

Cash is short right now but If I could get a Muffler shop to make up some pipes for me that would be a good way to check them I guess unless some one has another way to check them????

 

I took the initiative and pulled my Cats as I suspected one of mine is melted beyond use and is really bad Now I am looking for a new cat or a pair of pipes to replace them with.

This surely would make my engine act lazy and non responsive on throttle response.

Just my luck some one gives one of those by pass pipes away on here for free That's my luck a day late and a dollar short.

 

Sorry I can't help with the cat situation ........ I have a Euro car and it doesn't have cats ........... and Australia doesn't require me to put any on either .

Thank god it doesn't either, I understand that an engine with cats that has had the wrong fuel run for a even reasonably short period will put out far more pollution than a cat-less car anyway.

 

Well I am now shopping for one boy there expensive.

I live in an area were there not required too and I thought about just hollowing them out and putting it back together but if I sell the car the new owner would need them.
So I am shopping for one new or used one.

Supposedly there is some one in Vegas that rebuilds Cats I may try to get that done too I don't know yet.

 

....ohhh , , I just realized another guy on another thread seems to be describing the same thing as you. A melted cat obsructing the exhaust would certainly reduce performance enormously just like anything stuck in an exhaust.

Have you tried to get the melted bit out and refit it to the car just to see if that is the cause of the poor running ? (OK for me to suggest , I don't have to get the damn thing on and off again)

 

It was too far gone I had it Hollowed out I don't know what I will do yet though.

I am kinda thinking about a whole new system or at least new Cats.
The Car is going to need them any way now. That was probably me in the other post.

 

OK well an up date of sorts The Cat fire of the past has rendered my cats totally ruined so they have been hollowed out and reinstalled, At least till I get the car all up to snuff and running good then I can get new Cats.
Now when I went to start the car again to see if it helped the fuel pump is bad !!!!!!!

I CANT WIN!

New fuel pump in now and the car runs again although it breaths beater its still sluggish in revving in my opinion... GRRR seams to have a miss too, And a strong smell of fuel is very much present so I am back too looking at ignition problems, Just to make sure.

So I am starting over pulled the caps and wires started checking all the plug wires resistance one on rear bank was hi and two on front bank was hi 8k ohm rang rest were in 700 -800 ohm range.

I am thinking about a whole new set from local auto parts store but the lowest OHM wire I can find is 8k ohms will this hurt me electronic ignition system?

Can any one tell me how to eliminate all possible scenarios of ignition problems before I loose my mind? and my wallet replacing every thing!