Technical Starting Misfire

[Filthy]

Hi, Hope someone out there can help.

I have a prob with a 95 s. The car has a misfire when its started that clears within a minute. The car then drives without any fault. Sometimes the engine has refused to start completely, but has then started when tried after about 15 minutes. The car cranks over with no problems and has had new plugs, air filter fitted not long ago. I have had to clear the engine breather pipe as oil was being drawn into the air intake duct. The problem seems to be getting worse in the very cold weather but then again it will start even if the car has been left outside all weekend.....Very confused ! ! ! HELP...PLEASE.[V]

 

[HP]

The first course of action is usually to get it serviced if it hasn't been done recently, plugs - filters - the lot.

Unfortunately, starting on 3 cylinders and then 'clearing it's throat' to run on 4 is sometimes a sign of a cylinder head gasket on the way out.

Pete.
Cinq sporting 1242cc
http://mysite.freeserve.com/close_to_cracking_up/

 

[Rios]

Oh S***, that's what mine does. No not the Head Gasket!

Knew I should have bought something more reliable.

 

[Filthy]

Appriciate the response:

The motor wasn't due to be serviced untill June ( It's got a pretty good history ). I thought it may have been a head / ring problem but I stuck a compression tester on and all 4 cylinders provided similar results ( peaked at about 11.5 bar ).

The past 2 days we have had relatively mild weather and the car has started every time ( although a little bit lumpy ).

I dunno.....I'm running out of things I can check.....[!]

 

[Rios]

Hmm, they did the same to mine Filthy. When I had my lurching problem (see other thread in this section) they thought it was the Head gasket so stuck it through a compression test to make sure. It went through fine so guess I'm gonna have to wing it until the gasket blows.

 

[Filthy]

Now there's a coincidence. This motor was doing that lurching problem you describe when it was cold. I stuck a new set of plugs in and that was the last we saw of the kangarooing.

I wonder if the plugs have cured part of the symptom and not the real fault ? HHhmmmmm !

 

[Rios]

Tell you what we'll have a race then. Who can blow their head gasket first.

[!]

 

[Filthy]

I really don't think the head gasket's the prob. There's no evidence within the oil or water to back that up.

Can't help but wonder if it's one of the ecu sensors or wiring going bananas in the ( very ) cold. What ever causes this misfire it disappears so quick once the engine is running.

Anyone got any idea how much FIAT will sting me for having it plugged into the diagnostic equipment ?

 

[gaz.d]

Where about in the country are you Filthy, I had an independent fiat specialist hook my Uno up to a diagnostic machine, it cost me £25, and all the extra to sort out all off its problems!!!

Hope this helps[?][?][?]

Gaz[^][^][^]


Looks Good, Drives Sh!t.

 

[Filthy]

Cheers Gaz ! You may of got off lightly there.

My nearest FIAT dealer is in Oldbury, West Midlands. They want £60, yeah £60 , just to plug the bleedin thing in...They should change their name to Dick Turpin Motors ! ! !

Anyway TECH Q : Is the " wasted " spark strong enough to fire the engine ??? ie: is it possible that at the last service two of the HT leads have been reconnected to the right coil but the wrong way round so we have the stronger spark on two of the cylinders during the exhaust stroke ? If possible it certainly would explain a starting problem. I really could be barking up the wrong tree here.[)]

 

[HP]

The wasted spark should be the same strength as the main one, but if you want to check the leads, they should be like this:

Looking at the coils from the front of the car, from the back of the engine towards you the order is

4
1
3
2

Looking at the engine, the plugs are numbered from the cam belt end
1 2 3 4

Hope this is of some use to you.

Pete.
Cinq sporting 1242cc
http://mysite.freeserve.com/close_to_cracking_up/

 

[Filthy]

Cheers Pete,

Alas this doesn't appear to be the problem ( big suprise ! )

Anyway, got me hands on the car again. Tested everything possible with a multimeter...Got bored...Removed Head...There is the slightest gasket damage by the coolant gallery on 2 cylinders and and couple of valve seats aren't exactly fantastic. so hopefully when it's back together it'll cure the problem. Ah well !

Rios, Don't worry about doing the head. It's a piece of p;55

 

[Rios]

"Rios, Don't worry about doing the head. It's a piece of p;55"

Hmm, I dont share your optimism as I know naff all about cars. Still, I have some friends at a Toyota garage so looks like I better get it done before it dies on me. Good luck with yours.

 

[blackledge]

Cheers Pete,

Alas this doesn't appear to be the problem ( big suprise ! )

Anyway, got me hands on the car again. Tested everything possible with a multimeter...Got bored...Removed Head...There is the slightest gasket damage by the coolant gallery on 2 cylinders and and couple of valve seats aren't exactly fantastic. so hopefully when it's back together it'll cure the problem. Ah well !

Rios, Don't worry about doing the head. It's a piece of p;55

Same happened to mine, No2 Water jacket to combustion chamber leak and No2 Inlet Valve seat had dropped.

 

[fingers99]

Where about in the country are you Filthy, I had an independent fiat specialist hook my Uno up to a diagnostic machine, it cost me £25, and all the extra to sort out all off its problems!!!

I had an independent fiat specialist is the operative expression.

Howard will be too far away from the OP, could try Midland FIAT in Dudley (dunno where Oldbury is, now).

But HG and/or valve issue a real possibility. Don't forget to skim, re-cut the valves, re-shim.

 

[GoBe]

if it's not been solved yet I think the car will be dead. The OP getting on for 6 years old

but 10/10 for use of the search feature