Tuning Which lambda?

[Bushboy]

So, the head gasket can **** off. Not interested any more ... Well, it can wait anyway. Compression test came back boarderline so I'm leaving it and if it gets noticably worse (the starting issue that is), I'll do something about it.

My other running issue is hesitation and rough idle (and after today, random loss of 2 cylinders whilst driving once the car is warm :bang:... but thats a coil so no real hassle...) which is only present when the lambda is plugged in. Disconnect the lambda and the car drives and idles perfectly. Faulty lambda me thinks so I'm going to buy one.

Question is, which one to go for? Not really much on ebay for the mk1 sporting. Infact, nothing at all just searching for keywords.

Eurocarparts sell a bosch jobbie for an eyewatering ninety something quid. No thanks. They also sell another bosch which is the same sensor but with no plug wired. Its a much more reasonable fifty something quid, but will require me to wire the connector on from the old one.

Shop4parts dont list a 16v lambda :bang:... but the 8v and gt ones are stupid money too.

A google search came up with another company selling the bosch again for a more reasonable £75 but also a Walker sensor for £61.

What brand sensor do Fiat use as standard? Any to avoid or any that people can recommend? Also, wheres the best place to source one cheap? Ebay has let me down massively

 

[dave]

i thought head gasket was gone between 2 and 3

just go get lambda from scrappy a used oem one is better than a multi fit no plug one and the crap going through exhaust from naff gasket is going to kill that one any way

 

[Bushboy]

I don't know if the HG has actually gone or not. the variation in the compression test was only boarderline on whether I should worry or not (1-1.5 bar less on 2&3 than 1&4). Plus, with the lambda disconnected, it drives perfect so I'm pretty certain the hesitation is related to the lambda rather than any potential head gasket issues.

With the lambda disconnected, it seems to start better too, still not perfect but doesn't mess around for half as long as when the lambda is in.

Drove around 150 miles today. The outward journey with the lambda connected. Spluttering and hesitation, felt sluggish and idled really rough. Disconnected the lambda for the journey home and it drove perfectly. No hesitation or spluttering and the idle was spot on and smooth.

The only issue on the return journey was one of the coil packs cutting in and out every now and then :bang:... wish it would have just died, atleast then I could diagnose which one was dying.

 

[dave]

lambda is only supposed to do any thing when its hot i thought, did you drive to mums?

 

[Bushboy]

Nah went to the beach in north wales.

With the lambda connected, it does get noticeably worse once the car has warmed up. Especially sat in traffic. The idle was terrible when sat in traffic and seemed to calm once we got going again.

Checked local ebay for breaking locally and there arent any mk1 sportings/85s/cabrios locally. Doubt any of the local scrap yards will have any either. no specific fiat places near here.

You got one?

 

[dave]

wont 8v one do the job, i have about 3 in the shed with different length leads but the lambdas all look the same, am sure 1 of them came out of a bravo 1.2 16v

 

[Bushboy]

i dunno.

Not really sure how lambdas work but the bosch part codes are different. Dunno if the fiat ones are or even if they are different, whether others will do the job. Surely they all do the same thing anyway?

connectors may be different? Athough surely all Punto mk1 connectors will be the same

 

[dave]

mk1 and mk2 ones work different i cant remember why. i dunno about others, some have different part numbers because the cable is longer or shorter.
have you tried the Helz fix? https://www.fiatforum.com/bravo-brava/119607-time-year-again.html?p=1260818

 

[Bushboy]

MK2 have 2 lambdas so must be doing something different.

No harm in trying the Helz fix. presume its just dumping the sensor tip in a glass of coke for a while? Not gonna do any harm seeing as its ****ed already

Hmmm. Just checked the part numbers on the universal fit ones (where you fit the connector yourself) and they recommend the same part no for all MK1 puntos with Fire engines so the actual sensor itself must be the same, just different length cables, as you said.

 

[dave]

yeah but the 2 on a mk2 are totally dieffrent looking to the mk1s

measure your cable see if i have a match or longer one. local scrappy might give you one though be cheaper than postage.

hardest part is getting the buggers out even with a special socket. ive got 1 here that wont even come out gripped in a vice

 

[Bushboy]

Had one on an old cinq that I could never get out. Got a new downpipe in the end ...

I'll do my best