Hi everyone, I need help!!. Have just finished putting back together my daughters Bravo. It overheated, and warped the head, got a recon head, gasket set, water pump, stat, etc. The car was running fine before the head gasket went, but now with in minutes the plugs soot up and causes the car to surge and idle rough. I used a timing kit, and have rechecked the timing again today, all is good there. what could be causing the plugs to soot up so quick, thought I must have left a sensor unpluged or something, but everythings in. I'm at a loss
Thanks

Could it be runing a rich mixture?
forget the idle, for the moment.. how does it feel at higher speeds?

HI, yes I would say mixture is very rich, can smell the petrol at times. I havent run the car out, just had it on the drive ticking over. dosent seem as bad at higher revs. Could it possibly need learning again, (the ecu ?) Maybe needs resetting by Fiats ?. I had the throttle housing unpluged for 5 days. Have checked the timing yet again, looks good. Anybody with any ideas?

sounds like the timing is off to me..
but i'd definately have it down the road to see how it pulls.

Thanks for the reply, yea I'm thinking timing, but I locked the cams and had the rods in plugs 1 and 2. And once the timing belt was of, the crank wasn't turned at all, untill everything was back. Then I turned the engine over twice to check that all was fine and that rods were mid point with slot in cams lining up with cam locks again. At the moment it's set up with rods in 1 and 2, mid point, with no1 on downward stroke, (intake). The gap in the pully for the knock sensor is facing the bulkhead at sump level. Got a guy coming tomorrow to have a look, whats the betting it's timing? will let you know.

Just thought I'd do an update. Had a mechanic looking at the car today, "Ah yes, it will be your timing" he said. after 4hrs it was "ermm, your timing is ok, I'm going to have to go away and have a think about this" We did do the timing, in fact we did it 3 times, and not just checking, we took the belt of, lined cam locks up, lined pistons up, started up, just the same. No sensor faults showed up on hes gizmo, yes he is a proper mechanic, apparantly he has done these before. He didnt take any money, think hes gone of to top himself :bang::bang::bang:

Right.. lets look at this logically

we know the timing is ok.
If plugs are sooty and idle poor it suggests overfueling or inadiquate air getting to the combustion chamber.

So lets look at issues relating to the head change
1, Are the spark plugs from the original engine as others could be gapped wrong?
2, Are there any air leaks split hoses or wrongly piped hoses? Is the induction manifold bolted up tight and no air leaks?
3, Is the idle control valve from the original head?
4, Is the Egr valve from original head-is it clogged up?
Also
5, has the lambda sensor been disconnected-is it plugged in corectly?

Thanks for the intrest. Same plugs went in that was on before, but as they got sooty, I stuck another set in, (correct set), they also sooted up within 10mins. New inlet manifold gasket fitted, he sprayed something around this to see if it was draging in air, it was ok. he did a compresion test, that was ok. He took lambada sensor out, cleaned and put back.(he said he may try a new one tomorrow).Had top half of inlet manifold of today checking pipes and hoses, seem ok. When it was running today there were times (very briefly) that it seemed to clear. Im going to check everything again, mainly hoses and pipes, if a new lambada sensor dosent do the trick. We checked all connections pluging into sensors, seem ok. But I will check wiring, just in case a wire has pulled out from the plug. I will post again when its fixed, and what it was. In the meantime, anybody with any ideas?

also check the earth points, A friends car went to the garage once with a missfire and after a lot of searching it resulted in a poor engine earth, just a thought.

OK, heres the latest. got a mechanic that just works on Fiats, to look at car. checked timing, (again), no change. Changed lamda, temp, crank, sensors,etc no change.Checked earths, and cables, no change. Car was running, although very rich, when oops! head gasket goes again. guy said to change head, as it's under warrenty, which I'm doing, but he said that he dosent think that will cure why its running so rich. Now, could the knock sensor cause the car to soot the plugs up? Didnt touch the ECU or map sensor. Car is stripped down to block again, waiting on new head and gaskets. Got a tinny sound from exhaust when it was running? Also I fitted new hydrulic lifters, look the same, but going to get them checked before I refit. Maybe head faulty? over skimmed? valve props?

Hi, for those of you that are still alive when I started this, here is the latest. Got another head, checked my hydraulic lifters were correct,(they were), before fitting everything back. In the meantime I went through the wiring and took of every earth and cleaned and put back.I also fitted a new knock sensor, only because it's hard to get to when everything is back. Fitted everything, started 1st time,.....just the same, didn't realy think it was going to cure it, but it would have been nice. It starts easy, I have to keep my foot on the pedal to keep it going, it will run like this for maybe 3mins, then the revs increase by itself, then cuts out. Some input would be nice, lots of views, not many comments. Think I will book it into Fiats next week, nearly at the end with it

Throttle position sensor been knocked?
The other things is, as daft as it sounds you didn't pinch the fuel return line when you took the head off? if you left the line pinched it would do all you subscribed (Full fuel pressure constantly).
Also (never worked on a bravo of that age in my life but bear with me) Is the ignition timing controlled buy a crank pickup or a cam position sensor?
If so maybe that?
Honda's and most modernish Jap cars you can lock the idle and set the ignition timing manually . .

Booked car into Fiats Wednesday, only a short push! Spoke to guy that will work on it. He said he would check timing, said he thought it was set with pistons mid travel, but with number 1 piston on the up stroke? Ive always had it set on the down stroke? Is he right? Spoke to 1st mechanic again today, genuine guy, still hasnt chased me for money. wonderd if he had found anything out, no luck!. Fiat mechanic said I should have emptied the new tappets from oil by squeezing them in a vice before fitting. Maybe there holding valves open?

Any news?
I'm having the same issue after a head gasket change, have checked timing again and again etc.
Also been setting with no2 on the upstroke not sure it would even start the other way round?

Hi there, I have given up at the moment with the car. Fiats could not find out what was wrong. Had to tow it back, they had it for best part of a week. Started to suggest maybe a dodgy head, or injecters, or gasket fitted wrong, or ecu. They wanted to stripp it all down again to the block, at a cost of £800. Ive looked at the forums, and wonder if it just needs re-setting with the Fiat Examiner? but it was at Fiats, so you think they should know? (wouldnt they). How have you got on with yours? I used the timing kit when I did it, with number 1 piston on the down stroke. Fiats also checked timing, it was fine.

When the cam timing is off it registers a low MAP value ie not enough vacuum. This fools the engine into thinking its under hard acceleration and dispences with the lambda readings and uses mapping to determine fuel supply. Obviously its not the timing as thats been looked at.
The reading from the MAP sensor deserves a check though, I think it should be 1.0v on tick over,
on no vac (throttle blip) briefly to 4v
it only needs to be 1.3v on tick over to be a problem.
If reading is high suspect air leak in manifold, if ok check this voltage connects to the ecu pin ok. (could be pin bent?)
You dont say what engine and year you have so cant give pin readings.
Tony.

Hi, yea sorry everyone, thought i had gave these details. it's a 1999 1.2 16v engine. Fiats did say they checked all the pin connections. I had checked, and in some places renewed, the earths to engine and chassis. I'm thinking of taking the head of and selling it, as its a new exchange one. and scraping the rest of the car.

Kenjn4658 said:

Hi, yea sorry everyone, thought i had gave these details. it's a 1999 1.2 16v engine. Fiats did say they checked all the pin connections. I had checked, and in some places renewed, the earths to engine and chassis. I'm thinking of taking the head of and selling it, as its a new exchange one. and scraping the rest of the car.

Click to expand...

Hi,
I feel your pain,
we had to sell a good 6 year-old low mileage car ( not FIAT) with similar issues,
now - in hindsight I wish I'd tried this;
Disconnect battery,
then unplug the lambda sensor,
and MAF sensor, (+ a few other options I'm sure)
wait until the ECU should have "forgotten old faults" - a few hours..,
then start it up without touching the throttle.. supposedly the ECU will supply a nominal value for the sensors it receives no value from ( factory settings..!!)

in theory it will just run with a few nominal values in this "limp-home" mode,
then systematically replace sensor by sensor and see what / when things change,

what's the worst that can happen..??,

I know it's no consolation ..BUT I had no fuelling issues when I did the headgaket on a 2000 1.2 16V,
just major hassle with other bits..,

good luck, and let us know what you find..,
Charlie

TRY the temp sensor wiring also , as a non-connection here could leave the ECU thinking
it's minus 30 degrees C, that would make it run REALLY rich,
Charlie