General Finally given up (maybe) with my 1.6

[cptcuddles]

Firstly thanks for all the advice to my other posts.

Car lasted all of two days before throwing a P0170 light and drinking fuel. Was intending to sell in a couple of weeks anyway as wife as e new car arriving, but have decided as tax as run out to park up and sell.

Drove lovely then parked at work and from moment it started for return journey I could tell was running rich. Got home and long term trim was showing 99.9% hence the fault code. As I hate having to admit I'm beaten I've cleaned all air ducts and cleaned and reseated and set the throttle body and its now better, was wondering if any of the following readings look odd as they are from immediate cold startup after resetting ECU the longterm before starting showed +99%.

Short term trim -100%
Longterm trim -99%
Pre cat lambda 0.52V -100% short term trim
Post cat lambda 0.05 0.00% short term trim
Air pressure 13.3in/Hg
Closed Loop
Ignition advance 3.5 degrees
Coolant 100F
798rpm

After about 5mins of idling the short term trim had settled to swinging between 20% either way and the long term to -40%. Took the car for a brief run and the lambda settings were swinging all over the place when the car went into open loop which as was accelerating and decelarating I guess is normal but the P0170 code was now showing as a pending code and the car had gone sluggish again
Although I've promised wife I won't spend any more time looking at the car I just can't resist it. Going to check vacuum leaks next. Sorry for length of post

 

[Neverth]

If you can tell it is running rich, but lambda is still around 0.5V or alternating between 200mV and 800mV (limits for ecu to detect lean/rich), you may have a bad lambda or a little leak in the manifold.

Another possibility is injector stuck open (too rich, ecu cannot compensate) or clogged injector (oxygen in exhaust, ecu tries to run rich but fails as one cylinder is dumping oxygen for lambda).

*shrugs*
Good thing mine are single lambda systems.

 

[cptcuddles]

So much for giving up.

Saw a guy on youtube testing for air leaks by blowing cigar smoke through one of the vacuum pipes. Although I don't smoke I thought I've got to try this plus don't mind the odd panatella.

Found a leak were the plastic part of the manifold meets the the metal part the leak is on the bottom part of the port at cylinder no.4 . Put pipes back together and started car and sprayed WD40 around area of leak and engine note changed noticeably.

Car going on Ebay this weekend but hopefully I've now found the problem thanks to everyone that's helped especially Neverth

 

[Neverth]

The upper manifold separates quite easily, removing the oil filler tube is hardest part.
Plastic so mk2, it should have green O-ring kind of seals between the metal and plastic.

For cheap-ass solution try tightening it a bit and throw some self vulcanizing tape over it