MMM problem

[steve_79]

 My car stopped on the way to work one morning.
The local mechanic told me it would be the ignition module so i took it to him. Long story short he replaced the starter motor, ignition mod, belt, harmonic balancer etc before finally diagnosing a skipping timing chain.

When i got it back the light warning buzzer was going off the whole way home, it had no power and used 50l/100k's (normally about 10). The next day i decided to clean the plugs and noticed the plug leads were all in the wrong places. Once i put them back on correctly i had to turn the dizzy about 45 degrees to get it to start. Still using way too much fuel but now also shooting flames out the back after a few short revs, lots of black smoke still.
It has been taken back to be told there's nothing they can do to it.
Funds are stopping me from taking it elsewhere.

Checked for power to the maf sensor and found that it's not getting any power to it. Not getting any maf codes though.

Could this be a partially fried computer? Could this also explain the headlight warning when the engine is running? And is there anyway i can check this?

Or is there just something else that i'm completely overlooking.

Thanks for any help.
Steve

[gtc]

he replaced the starter motor, ignition mod, belt, harmonic balancer etc before finally diagnosing a skipping timing chain.

...

The next day i decided to clean the plugs and noticed the plug leads were all in the wrong places.

And this guy has the hide to call himself a mechanic!

[VET-005]

I would start with the basics first to rule out some issues.

1. Invest in a Hanes workshp manual for the C4 if you don't already have one, they are not that expensive and will give you step by step instructions on how to do things and perform checks

2. Get the car on TDC (top dead centre)and check where the rotor button is facing. It should be pointing in the direction of #1 cylinder and at #1 spark plug lead when you put the cap back on.
make sure the timing is not 180deg out. If so you will have to pull the distributer out and make it right.

3. Put new plugs in it and measure the resistance in the leads to make sure one of them is not crook.

4. Check timing using correct procedure where you bridge A,B on the diagnostic link to put the car in diagnostic mode.

5. The chances of it skipping a tooth on the timing chain are slim unless the vehicle has loads of k's and the chain is severly streched and it happened while you were driving it very hard. This is more likey to happen to cars with timing belts than chains.

6. Once you have ruled all these things out then proceed to do a codes check and see what codes the vehicle is throwing. The ECU can diagnose everything but itself.

7. If no codes are present and problems still presist try and borrow a computer off someone juts to try and see if this fixes your problem before you buy a new one.

Hope this helps.

Sash

[77CVT]

:banner:

Why replace a balancer if the timing wasn't out?

The module in the dizzy will retard the timing about 20 deg - I blew mine somehow when I rebuilt my engine and was running it in.

Start at the leads and check they are all in order, TDC, check No1 is just past the contact point for the No 1 lead.  A crook lead will won't make it stop....unless you got 5 crook ones.

Your cold start injector could be stuck open.

Pity you are not close or we could swap computers.

[steve_79]

I've got the gm factory workshop manual. Bit hard to follow at times though.

The dizzy is pointing to #1 at tdc when you turn it about 45 deg's

It's got about 160k Mls. The teeth were worn off the TC sprockets but it didn't break so when i did my roadside diagnostics it was throwing a spark.

It is throwing codes about electronic spark control but nothing about throwing 5 times as much fuel as it should or the maf sens not working.

The balancer had spun but i had been timing it by ear and feel previously which worked alot better anyhow especially once you reconnect the elec spark control wire.

 The ignition module in the dizzy was one of the first things he replaced but i suspect it was a holden unit. Are they different??

 The leads were all wrong when i picked it up, but that was the first thing i fixed.

 How do i diagnose a cold start injector stuck open, that could explain alot, however i think it's in some sort of "limp home" mode.

 And 77CVT, We are alot closer than you think... I moved near helensvale about 18 months ago, just haven't updated any details... Otherwise it would of been wipped arount the corner to cameron quick smart..
 If that computer swap thing is at all possible it would be muchly appreciated, she's been parked in the garage for about 6-8 mths since this all happened and i miss her so.


   Thanks guys.

   Steve

[bfit]

Some good advice so fare
any good  mechanic would start at the basics  
Air
compression
timing
Fuel
 every thing else is and extension  of these  four basics

IF
the timing did jump, then first check  the compression
 there is a possibility that you could have bent valves

now black smoke
1 lack of air
2 over fueling
2 to much advance ( over fueling  can hide the pinging )

 get a good work shop manual and have a read
some  times a little knowledge can lead you astray so talk to  others and get some direction
 
You will be able to do a lot of this  your self
If you don't want to then you will have a better understanding
 and hopefully know when you are getting BS from those who are doing the work for you.


 One could write an ease here

I did not read  which state you are in
 
IN NSW  motor repair is under the umbrella of the MTA
 other states will have similar bodies
you may  be able to get some help  

Bob




 

[Scott]

Since you are on the Gold Coast, take it to Corvette Performance at Nerang. He knows his stuff and should be able to chase any electrical problems down.  There are always a few C4's in there when I drop by.

[77CVT]

Mate I am happy to help.  It sounds like a good excuse to cruise down the coast!

We can swap MAF, computer or whatever else you need.  I'll send a U2U

[77CVT]

Mate I can't U2U for some reason.  

My No is 0422976572.