Exhaust gas leak. Suspect manifold

[jackherer 543]

It doesn't need either to not smell of fuel or exhaust fumes, my car doesn't have them.

 

When we left Emerald it seemed fine so something must have changed surely?

[jackherer 543]

Bring it round some time and we can put my wideband on it if you like.

[Telf 222 2 Cars]

I spent a bit more time on this yesterday tightening all the breather clips etc. This morning the car won't idle ... So I've let the throttle screw out a little ( it was fully tightened during the mapping) and it's idling normally. 

 

Maybe I've had a unmetered air/breather leak?

[jackherer 543]

I think the only hose that will let air in to the engine side of the throttle is the plugged one under the inlet.

 

You can test that, does the idle change if you take the oil filler cap off? If it does then you know a breather hose leak will do the same.

[Telf 222 2 Cars]

Mate I tightened up every single oil and air hose so something must have been letting air in/out. I'm pretty pissed off with it all now and getting close to ripping it all out and reinstalling the old system. I need a car I can drive without all this bollocks going on!

[jackherer 543]

Air leaks would be causing you more problems with Jetronic!

[Telf 222 2 Cars]

so if i fit a O2 sensor and activate the MAP will it make any difference?

 

[welshpug 1,621]

you'll need a mapping session if you want to activate the map for any load sensing/compensation.

 

as for an o2 sensor I would get one fitted but not use it for correction just yet, but use it as a diagnostic tool to see if it is running a bit lean, which the condition of the plugs seem to suggest.

[welshpug 1,621]

another thought also is that the ticking noise specifically under load could be pinking, which would make sense if its running lean, it may be a faulty tps not showing it needs more fuel to go with the air its getting, an air leak would more so show under light throttle loads given the higher vacuum present and that there is no manifold pressure nor air flow meauring going on

[Telf 222 2 Cars]

Well today post everything I took it for a run. It behaved quite well. It does  have a whiff about it but not too bad . I don't know what to do really. It pulls like a train ( can easily out run my 207THP 175)  so what to do?

[jackherer 543]

Bring it round and we can connect my laptop and wideband to see what is actually going on while you drive it.

13 hours ago, Telf said:

It pulls like a train ( can easily out run my 207THP 175)

It might be time to get the inlet ports walnut blasted in that case...

 

They should be pretty similar TBH!

[Telf 222 2 Cars]

I will bring it over mate when I get a spare 5 minutes

[tartanbloke 35 1 Cars]

Dude, I had a petrol smell when the windows were down and the sunroof open, which I identified to be the inlet fuel hose from the pipe going under the vehicle to the rail. It appeared the previous owner did a bit of a bodge job, which meant it was not fully tightened where it connected to the pipe (under the servo) and when driving the air flow pulled the fumes up and over the vehicle.

 

Might be a red herring but could be an idea.

[Telf 222 2 Cars]

Rgr I will have a look see . It's all new hoses on mine as I've just rebuilt it. Maybe it's come loose!

[jackherer 543]

We haven't got to the bottom of this so I'm going to summarise everything that's happened to date to see if anyone can suggest anything.

 

So firstly Paul rebuilt a totally standard 8V 1.9 engine and was thinking of buying all new engine management for it (e.g. AFM, distributor etc.) but the prices for those parts are very high so I suggested he buy an Emerald ECU instead.

 

He then built a loom and fitted the ECU with all new sensors etc including a MAP sensor.

 

I tweaked a few settings and got it fired up on a base map supplied by Emerald.

 

We took it to Emerald who spent a day mapping it. The only issue we had on that day was an air leak where Paul hadn't quite blocked the redundant SAD port under the inlet manifold. Emerald turned up a plug for that before mapping got started. It made 1 or 2 bhp over book figures and everything seemed good at this point.

 

Then Paul MOT'd it, I understand the tester had some trouble getting to pass the emissions test but this wasn't looked into at that point because the tester just did Paul a favour and put the probe into another car...

 

After a short period of time Paul said the car seems to smell of fuel so I plugged my laptop in and saw that the MAP sensor wasn't reading anything despite being connected correctly. I suggested he buy a new one which he did.

 

But he was still reporting a fuel smell so I plugged the laptop in again and the new sensor wasn't showing any values either. It turned out the ECU wasn't configured to use it, Emerald had gone down the TPS (alpha-n) route instead without telling us. After some discussion at this time I learned it hadn't passed the MOT emissions immediately after being mapped so I said he should take it back to Emerald.

 

I joined Paul when he took it back to Emerald and they did another full mapping session on it and confirmed it would pass a MOT test based on their wideband.

 

Then we drove from Emerald in Norfolk back to Ipswich and it seemed OK to me at that point.

 

But as can be seen from this thread Paul *still* has a fuel smell problem.

 

As you will have read he tightened some breather hoses which must have done something because the cold start idle deteriorated.

 

He came here with it yesterday and I put my wideband on it. The AFR was actually very lean to start with but it turned out Paul had wound out the idle screw on the TB to help the cold starts after tightening the breathers. After screwing that back in the AFR was about 14.7 at all the RPMs we tried it at. This was all stationary in neutral. I also plugged the laptop in and checked all the sensors had sensible values which they did. We ran out of time to try anything else.

 

There is still a problem and today Paul has taken it to an MOT garage where apparently their equipment shows the hydrocarbons at about twice the limit.

 

All I can think is that something must intermittently change, I have maybe smelled fuel once on the way to Emerald the second time, other than that it seems fine to me. But Paul tells me that everyone that he speaks to tells him it stinks and the MOT equipment apparently has it at twice the limit so something is going on.

[Telf 222 2 Cars]

That's about right Kieran. The exhaust had a blow on it which we sorted today but that made no difference really. I've taken it to Hangar111 which specialises in Lotus but has a rolling road. It is booked in for a diagnostic next week. They have said ii doesn't seem right, smells bad and appears to be misfiring slightly. I had the plugs out recently but all look the same -no overfuel as such ( eg a injector stuck open etc). 

 

I don't know if it's something to do with the engine wearing in but I doubt it. I believe Emerald have mapped it with a air leak in situ. As the map is essentially rpm V throttle this would surely throw the fuel map out under load? I dunno. 

 

You have seen the reply I got from Dave Walker at emerald . I don't think they will look at it again even though I fundamentally think the map is wrong.

[Telf 222 2 Cars]

I have also checked all the fuel hoses for leaks or loose connections. It's all correctly assembled

[jackherer 543]

I just had a thought, I have copies of both maps you left Emerald with so I am going to compare them, it'll be interesting to see what changed after the second mapping session...

[Andy 105 1 Cars]

My thoughts.. AFR looks correct, although the plugs do look as if it is running weak. High HC values suggest incomplete combustion which could be a late spark at tickover. Depending upon how Emerald have set up your engine, they are quite keen on getting the engine to tickover at 900 rpm at almost no advance, and then then allowing the spark scatter function to control the tickover as the load varies ( alternator etc ) .

However, you can look at that just by connecting up a laptop with the Emerald software installed and look at your ignition map. The fact that your exhaust was leaking will have wrecked fuelling and probably caused the smell you reported before, but no real help now . One other thought is that ordinary rubber fuel hose is not resistant to fuel vapour leakage, and will cause a bit of a smell, as will a very tiny fuel leak. 

My starter for ten .

 Andy

[jackherer 543]

So I wonder if there were multiple minor faults (i.e. leaking exhaust, cracked manifold and leaking breather hose) during both mapping sessions that have then been fixed therefore putting the calibration out each time?

 

I think the fuel hoses are BakerBM ones, has anyone else reported fuel smells from those?

[Telf 222 2 Cars]

They are baker hoses correct

[Telf 222 2 Cars]

Ok so here is the emissions today as I drove it.on the ramp after seeing you Kieran

[Telf 222 2 Cars]

And here is the figure when I turned the air screw on the throttle.

[Telf 222 2 Cars]

Bearing in mind as I said after tightening the hoses it wouldn't idle unless I opened the screw. When I saw you and we got the reading the screw was fully in. When I left work at 2200 last night it wouldn't idle at cold 

[jackherer 543]

Like I said when you were here it wont idle from cold without an idle control valve. You'll either have to fit one or feather the throttle for a minute or two from cold.

 

That second chart is an MOT pass isn't it?

 

The non cat MOT test needs the CO below 4.5% and the HC less than 1200ppm.

 

The first chart is a slight fail on the CO but the HC is still OK.

 

For cars after 1992/1993 with cats the HC needs to be below 200ppm but for a 205 GTI it's a 1200ppm limit.