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156SW JTD 16v m-jet Progress thread

5K views 116 replies 10 participants last post by  Chris155 
#1 ·
Cut and pasted from my "help" thread;

As some of you may know, I have a new project car to fix. It's a 54 plate 156SW 1.9jtd mjet.

It also has an alfatune 175bhp remap. I mention this only for info, not because I think it's got anything to do with the problems I'm about to describe.

It's recently had problems with its injectors, no 1 failed wide open, causing the car to grind to a halt. Testing ALL of the injectors showed this to be the problem (2,3 & 4 were OK) and the worst was assumed initially, that the engine would be scrap.

However an injector was cobbled together by a specialist and fitted, the engine ran, albeit badly. It felt like it has a misfire lacked power and smoked. A lot.

It was a this point, the owner gave up, bought a Brera and sold it to me.

I bought it expecting to find that it has a bent con rod but I've fitted another replacement injector supplied by the seller that is assumed to be good. It now runs like it should, ish.

It feels like it has it's full compliment of ponies but it has a slight misfire which can be heard at the exhaust pipe but isn't noticeable otherwise.

I also still smokes, a lot, when revved hard. Black smoke.

No fault codes are logged.

I disconnected the MAF, which made no difference to the way it ran, so we swapped that for an unknown replacement. No Change. Same for the MAP sensor. But then I don't know if the replacements are any good.

The injector on 1, the one I replaced needs a new seal, combustion gases are leaking past it, which may explain the slight misfire.

It clatters, more so than I would expect, occasionally after being left to idle then revved hard.

That was tonight but after that, we gave up. It was dark, 2.0deg c and raining...

Next up...

Code the replacement injector in to the ecu and make sure the other 3 are coded right.

Check the EGR valve?

Fuel pressure values.

And maybe a leakage test for the injectors.

The engine problems are now fixed. ish....

I had nothing to do with it.

I didn't fix anything.

My (Pensioner) Dad has done it all. :(

This is why:

https://flic.kr/p/qqDMct

I've had that plate and screws taken out of my arm. I had the a phone call tues 2nd dec asking if I could come in, plate out 5th Dec and I'm still out of action.

It's very frustrating. But in addition to fixing the known issue;

Excessive smoke and poor running, fixed with;

2nd hand, proven injectors
New MAF
New MAP
2nd hand fuel pressure regulator
New injector seals

My dad has been busy fixing;

The seized broken rear wash wipe
Failing windscreen wiper mechanism
(Very)Broken under tray

He's also in the process of upgrading the headlights, and he's checked the floor for rot (all good! :) )

I'm sure he's done more....

He has. Mirrors off, corrosion cleaned up... Apparently this is a lengthy manual process.

I'm feeling somewhat guilty at this point.

My Dad also reset the cam timing, which was slightly out.

Xmas update...

We (i.e. my Dad) found a cheap replacement fuel pressure sender on ebay and fitted that. It was a GM part with a different Bosch PN but off what is effectively the same engine. Fitting that cut down on the amount of smoke under hard acceleration but also affected performance - it felt slightly down on power.

It did, however give a more realistic mpg figure of around 55mpg rather than 68mpg.

Thinking, that perhaps this might be a promising solution we (my Dad) sourced and fitted the right part. And it went back to trailing a thick smog behind the tailgate... For about 20 miles. It seems that it's adjusted itself and whilst it isn't great, smoke output is back to where it was with the GM sender. Performance is improved though.

It's also back to the unrealistic 60+mpg...:roll eyes: It's got half a tank shown on the fuel gauge and it's showing a range of around 500 miles... Yeah. Right.

We (my Dad) also replaced the thermostat. It's still very slow to get up to temp compared with the GTA though. I think the temp sender is faulty? The new sender that came with the stat is the wrong one though (4 v's 3 pins). Next part I guess.

We (my Dad) has also sourced a bi-zenon projector lens conversion kit from eBay. I had a long argument with someone on here (their now banned) about the merits of the cheap projector lenses v's the expensive ones from retrofit source. At the time I'd ended up with the retrofit source ones but the cheap ones my Dad has sourced for the 156 are EXACTLY the fecking same bar some minor extraneous mounting bolts. They were about £15 quid each IIRC. Well worth it even if they come in LHD configuration to begin with.... Then again so did the retrofit source ones. :roll eyes:

So that's coming too, it needs them. The standard filament headlights are like having cataracts.
We replaced the offside track control arm this weekend. It felt like it had movement in the ball joint, replacing it has improved things but there is still a clunk if you rock the rack left/right. Don't know why...

IMG_4363 by chris147gta, on Flickr

IMG_4366 by chris147gta, on Flickr

IMG_4370 by chris147gta, on Flickr

IMG_4374 by chris147gta, on Flickr

IMG_4375 by chris147gta, on Flickr
 
#2 · (Edited)
Which is pretty much where we're up to so far. It wasn't right though. There was a problem with one of the xenon units so we had the bumper off to replace it. On putting it back together I started it up and it was belching out smoke and wouldn't rev. So I did the obvious, fix all solution. Held the throttle down to the floor...

Which sorted it, suggesting a problem with the egr valve.

My Dad had been eyeing up egr delete kits made by the Poles, this incident provided the impetus to try one;

In bits... AGAIN...

IMG_4455 by chris147gta, on Flickr

And this is the kit;

IMG_4460 by chris147gta, on Flickr

'Course there isn't enough clearance between the and the erg valve to slide the plate in...

IMG_4456 by chris147gta, on Flickr

Which meant taking the egr valve off. And then faffing with helicoils because 2 of the threads that hold it on were stripped.

IMG_4462 by chris147gta, on Flickr

But I'm pleased to report it's now running really well, only (slightly) smokes under hard acceleration. And it's getting better... You have to work hard with the gears but OMG, it's seriously quick cross county... I reckon it would stay with my GTA on a and b roads...

Only problem is, the brakes can't cope... And the mpg has gone down as it's now happy to rev past 3k. But that's really my fault, not the car.
 
#3 · (Edited)
I spoke too soon... I think the turbo is on it's way out. The whine / whoosh type noise under acceleration is getting worse. I thought it was the fuel pump but using a stethoscope (aka long screwdriver) we've (My Dad) narrowed it down to the turbo.

I'm not sure which is worse. Either in terms of labour or parts?

Is the 170bhp JTD turbo any different?
 
#4 · (Edited)
Day off today:)

I think I've mentioned that there was a vibration in the drivetrain under hard acceleration. It's worse with someone in the passenger seat. The 17" multi spoke wheels it came with were a little out of shape but changing them to the Ti wheels made no difference.

So, despite it having had some work on the drive shafts (new spiders) we started looking at these as the root cause. Running it up in gear with the wheels off the ground upset the abs but also showed that the drivers side driveshaft may be bent.

Which prompted my Dad to have a look at the prices of replacement driveshafts. Turned out a new one, including the mid shaft was under £50...:eek: So that was a no-brainer. It turned up Monday just gone.

IMG_4529 by chris147gta, on Flickr

The suspension pretty much fell apart, having been previously torqued up correctly. (see below)



IMG_4532 by chris147gta, on Flickr

IMG_4533 by chris147gta, on Flickr

Old v's New...

IMG_4531 by chris147gta, on Flickr

Drive shaft back in and nearly back together...

IMG_4534 by chris147gta, on Flickr

And then I went to put the upright back on. Torqued up the bottom arm, then found that the treat on the upper arm ball joint was trashed (not a real problem) and there was movement in the bushes. Hmmm Bugger. I argued with myself about whether or not to replace it - we have spares in the garage and eventually decided to take it all apart again.

TBH, it wasn't that much of a chore as the bolt though the suspension strut fork is free and the fork will separate from the strut.

IMG_4535 by chris147gta, on Flickr

IMG_4536 by chris147gta, on Flickr

We replaced the arm, put it back together (again) and went out for a quick test drive.

*touch wood* The vibration has gone. :D
 
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