The Troublesome'maro Strikes Back...

Titsy · January 26, 2007, 06:59:16 PM

It seems that after a few trouble free miles it is time for the 'maro to have its revenge... I move her down the drive this morning so that we could have some fence panels delivered behind the gates. While I was moving it I noted that it didn't sound quite right. I didn't have time to think about it this morning, but when I moved it back this evening I clocked what was going on. From the sound of the idle, and the smell of the exhaust it has dropped the ignition on a cylinder. Not sure at this stage if it's a lead, plug, or the dreaded optispank, but that's my job for tomorrow.

Am planing on working my way roung the injectors and disconnecting one at a time to see which one doesn't effect the idle. That should tell me which one isn't sparking and i'll work from there....

The bloody thing doesn't like me I tellsk ya...

If it's the optispank then the shiny-things budget is going towards coil-per-plug...

EDGE · January 26, 2007, 07:01:47 PM

Quoting: Titsy

Am planing on working my way roung the injectors and disconnecting one at a time to see which one doesn't effect the idle. That should tell me which one isn't sparking and i'll work from there

dude.. if you're gonna do that PLEASE use long pliers... I almost got fried pulling the lead of a car on the dyno without pliers... hurts like a BIATCH

bad luck though.... if its not one thing its another....

Titsy · January 26, 2007, 07:14:13 PM

You mean fried as in hot or shock?

The injector leads (which will let me work out which cylinder isn't sparking) are nice and 'easy' to get to at the top of the engine. The plan is to spend no more than two minutes with the engine running working out which cylinder is duff and then kill the engine before things get to hot.

Then I can set two in the duff cylinder checking firstly with the old screwdriver electrode trick (warning: risk of high voltage shock, always ware ruber gloves when conducting this test

) to see if the if anything is getting to the plug, and then either pulling the plug or the lead dependent on that...

EDGE · January 27, 2007, 04:19:20 AM

sorry dude... that was me not reading properly at midnight... i thought you were gonna unplug the HT leads one at a time.... and fried as in shock yes...

Titsy · January 27, 2007, 04:32:03 AM

LOL... You know how hard it is to get to the plugs on an LT1 4th Gen, hence using the injectors to find the cylinder first...

art b · January 27, 2007, 06:03:08 AM

ya can touch the exhaust manifold ,to see which cylinder is not workin

ie cold at one point

Titsy · January 27, 2007, 08:04:03 AM

Well, I set to this morning, and found nothing wrong....

All seems to be running fine this morning!?! Maybe I heard something that wasn't there, or maybe it was just grumbling because it had sat all week in the freezing cold.... who knows... I'll just have to keep an eye on her... But for now, she's running just fine...

FUBAR · January 27, 2007, 08:05:28 AM

Quoting: Titsy

But for now, she's running just fine...

Good to hear m8

Fieldy · January 27, 2007, 11:00:53 AM

might just be the turn in weather.....let us know!

55starchief · January 27, 2007, 11:13:21 AM

It could have been over compensating with the choke mate, that would give a rough idle and a rich smell. Did you sort out the EGR valve yet?

ianjpage · January 27, 2007, 03:46:06 PM

Quoting: 55starchief

Did you sort out the EGR valve yet?

dont mention frickin EGR valves

first - glad to hear it all working again, although vicky be disssapointed she not get her car yet

Anyhoo - frickin egr valves - had problems last sunday with the GMC Safari starting, after chatting to rebeltrucker, he said prob egr valve, so stripped air filter out and gave it some gentle persuasion with a big ol hammer - ran fine, drove to me mums did brakes, drove back no probs.

OK i think - MOT it cos it out of MOT - so speak to me mate and they only one he got is 7AM this morning............so i get up fricking early (6.15!) and go to drive to mot.......f*****K thing wont start - same problem.....

So at 6.30am in the morning i am there, with torch in one hand dismantling the air cleaner and beating the cr*p uot of the egr.......after 30 mins i give up (having by this point flattened the battery so am now jumping the van from the cobra).

Go out this arvo to try and fix it - f*****k thing works - arghhhhhhhhhhhhhh

Titsy · January 28, 2007, 06:09:06 AM

I thought that the EGR system only kicked in once the engine was warmed up...

This sounds more like an automatic choak problem... You need some 'Start-Ya-Barstard'...

philoldsmobile · January 28, 2007, 06:26:36 AM

all HT leads good and secure?

i cant see any reason for a working healthy engine to drop a cylinder, regardless of conditions..

prob something simple though.... although i cant be sure, i seem to recall that opti sparks tend to produce a stutter and flat spot before they die completely, rather than drop a cylinder as they generate a weak spark over all cylinders rather than just one....

55starchief · January 28, 2007, 08:28:11 AM

Quoting: philoldsmobile

i cant see any reason for a working healthy engine to drop a cylinder, regardless of conditions..

We were chatting last night and im pretty sure it was over choked, the car had been sat for a week and got uber cold, the computer probably thought the temp was a couple of degrees colder so tried to richen the mixture hence the poor idle and excess fuel smell.

philoldsmobile · January 28, 2007, 12:02:33 PM

hmm.... inlet air temp sensor dicky? any codes?

Titsy · January 28, 2007, 12:08:33 PM

Nothing at all.... I letteral only drove it a few yards in each case...

55starchief · January 28, 2007, 12:15:18 PM

Quoting: Titsy

Nothing at all.... I letteral only drove it a few yards in each case...

well that wouldnt be long enough for the choke to have cut out so in my opinion points to that being the problem

philoldsmobile · January 28, 2007, 05:20:27 PM

ummmm.....
not sure what you're refering to as choke? it hasn't got one...

the cold start table should never permit overfueling to that degree, one of the big bonuses of injection is that it runs 100% all the time, regardless of temp.. if it is that rich, something is wrong, simple as.

4th gens in canada and new england area would experience FAR worse conditions on a regualr basis, so if this were the case, it would be a widely critisised problem

i just cant accept that a modern car running correctly will EVER run on 7 cylinders, it just wouldn't be acceptable..

Titsy · January 28, 2007, 05:33:40 PM

I'm not convinced there is a problem, I may well have imagined it, I am a little paranoid now....

I couldn't find a thing wrong when I went looking....

philoldsmobile · January 28, 2007, 05:43:05 PM

if a sensor is old, sometimes they can give slightly bad readings...

if its an air temp sensor, it may be telling the ECU its colder outside than it actualy is, so the car would be fueling for a colder start than is nesicary, an over rich mixture gives a verry 'chuggy' idle

can you read the air temp from your laptop?

might be worth reading the cars sensor and comparing it to what the temp actualy is..

Titsy · January 28, 2007, 05:50:21 PM

Can do.... Will set up a thermocouple and compare readings...