VT Hard Start on cold and sometimes hot

[jazza15]

I have been pondering what could be causing my VT II to have a hard start for quite a while now and just can't seem to nab what the problem could be.
I was thinking injectors, but i would say that it improves, almost to normal when hot, but sometimes not as good.
Maybe electrical? I checked all the wiring and couldn't find anything loose or defective visually.
The fuel delivery system: My fuel pump works for the specified 2 seconds when turned to the 'on' ignition position and i can hear it working while the car is starting.
My mate suggested that if it is the pressure regulator, then the engine should struggle if i plant the foot and take it to 80km/hr in 3rd (coughing/spluttering etc.) due to the fuel pressure deficiencies...well it didn't.
I have swapped my fuel pump relay with the starter relay, which is the same, so it isn't that.
A car struggling to start in the mornings is usually a sign that your battery is going flat, but i have recently replaced my battery (and ****ty holden stock terminals!) with a heavy duty (...champion?) battery after my car completely would not even crank. it fixed that problem, but still took a while to start, which brings us a few months forward to today.
It cranks well i would say, the momentum really builds up sometimes, so much so that i think the starter is spinning the engine faster than the engine idle speed.
Anyways, some helpful advice would be greatly appreciated as i am fairly stumped at the minute, even the Holden workshop manual "hard start diagnostic" section can't seem to help me pinpoint the problem.

[vtmanualv6]

How does the car actually run? Normal, not the best, bad or what ? For a engine to work, it needs air, fuel, and spark

For starting issues air wouldnt be much of an problem because if it was air it wouldnt run right and have bad overall performance

Fuel would be the thing to look at for starting, try checking your fuel pressure with a pressure gauge, change your fuel filter, but as i said hows the car running ? Really need more info

Spark could also be a key to the answer, maybe faulty plugs, coil packs, or leads, but to get an answer we need more info

[willnott]

Im having simular trouble with my VX, takes a few goes to start. When it is running it idles good. Tried all the easy things like spark plugs and fuel filter; my leads are reasonaly new, so I am to believe it is one of two things fuel injectors or ignition coils. I'm still yet to solve my problem but will try injectors first this weekend and see from there, unless there are any suggestions as to what else it could be....

[Benboy]

It's no good just randomly replaing things. You need to check each component and ensure that it's performing to specifications. For example, check the coil pack, if it's working OK then move onto something else, perhaps plugs/leads, if they're OK then fuel system etc. Don't waste your money replacing things that might not require replacement. If in doubt or lack of confidence then go to a mechanic or get RACV, NRMA, RAA etc to diagnose for you.

[don0xer]

CAS 99% sure, happens to every commodore

[jazza15]

You're really digging up an old one here. I must have repeated this question a few times since i first posted this one.
My mechanic couldn't diagnose the problem, even though they said they did, so I will probably be taking it back there next week, this time hopefully for a free diagnostic.

Can you elaborate on how the CAS failing can affect the starting time, but not the performance or economy? Any more details/cost?

[don0xer]

the CAS(Crank Angle Sensor) sits behind the harmonic balancer(big pulley on bottom of engine) next time you have trouble starting it try pouring some water all around the harmonic balancer as this sometimes helps to start it... i dont know the reasons why but it just does lol.

its a bastard of a thing to replace since the harmonic balancer has to be removed first which is really tight. im sure most mechanics have done it plenty of times and could do it alot quicker than somone who hasnt done it before but i wouldnt have an idea on price...

[jazza15]

Oh yeah, i've had that suggestion before, but wouldn't the CAS failing result in other symptoms such as poor performance due to poor crank angle sensing being sent to the ecu? I've only noticed a hard start and that is it.
Cheers

[willnott]

I had RAA out today to help diagnose the problem with hard start. It appears to be a fuel blockage problem which he suggested a change in fuel filter (did this earlier in the week). He tested the AMP draw of the fuel pump - it should be around 4 but mine was 9! His next suggestion was to change a possibly faulty fuel pressure regulator - early quotes indicate a cost of around $100 to replace myself.
Hope this has helped someone!!
Cheers, Willnott

[jazza15]

Let us know if it is the fuel pressure regulator. That was one of my initial possibilities, i got one from the wreckers, but didn't bother going through the trouble of fitting it as it is a bit of a job.
So let us know if that's it, as fuel pressure regulator ticks a lot of the boxes for my problem.

[Ozzie]

do you get any shaking whils driving?

Possible coil pack problem, fuel pump problem, lead problem.
How long since you gave it a GOOD service?

[jazza15]

I have a steering wheel shudder, caused by something else, as explained in my other posts.
If my coil had a problem wouldn't i be mis-firing and having horrible problems of that nature?
I replaced the leads a short time ago.
If the fuel pump had a problem, it probably would have worsened by now and just stopped working. Fuel pumps are either working or not working aren't they?
I just took it into a mechanic for a good service. He's a good one because my mate chose to do his apprentiship with him for that reason.

[Ozzie]

Fuel pumps can be funny things.

Yes their either working or not working but if the voltage is low it will be working but not working.
First things first.
Check the voltage from the battery and work your way back. (although you mentioned the starter kicks over nicely so this may not be the problem)

Check for spark.
Check for fuel. (make sure theres no water in the fuel tank)
Wouldnt hurt to throw a bit of metho in the tank along with some injector cleaner.

Check the MAF sensor connection is'nt dirty. (wouldnt hurt to spray some throttle body cleaner down it. just make sure theres spark first)

[jazza15]

The fuel pump voltage is sounding to be pretty accurate.
The mechanic just cleaned all the air intake system, so it shouldn't be the MAF sensor. Considering I just changed my ignition leads and plugs, with no change to the problem, I would be leaning away from that sector.
Battery was changed early on.
I think it is either the fuel pump voltage, some engine temp or coolant temp sensor, or something very simple that has been missed all along.

[jazza15]

Fairly sure i have now diagnosed the problem.
I told my problem to a mate and a light globe went off in his head, he said he had the same problem with his commodore previously.
The problem being the ball on the key head not making good enough contact with the ignition barrel cause by generl wear over time and most commonly found in vt's that have done over 200,000k's.
So i had a look at the contacts and you can't really do much about them, but what you can do is puch the key in hard as you turn it to start it.
I found immediate improvement by using this method. starting time has been reduced to an absolute minimal delay.
Now my next problem is fixing it in the near future.
I have read a bit about changin the ignition barrel and it seems a bit of a daunting task.
can i just replace part of the ignition barrell?
what would be the best method to fix this contact problem.