91 Esprit won’t pass emissions- Ontario Canada

[Devilish]

My 91 Esprit won’t pass an e test. Had the test done last year and the limit for CO was 1...my car blew a 7.

since then I have replaced injectors, air filter, fuel filter, spark plugs, ECM, coil packs, MAP sensor, O2 sensor, added a 3/4” catch can etc...stupid thing today blew over 10 on the CO test and 1200 on HC!!

its dumping fuel and I have no idea why?

test results below

[Barrykearley]

You need that car on freescan or espritmon.

O2 sensors should take care of reducing the emissions with the cat. Are the o2 sensors good quality ones or eBay China ones? 

Air leaks on inlet can cause abnormalities - but you would be finding it running oddly if that was the case.

is the TPS set correct? The IAC set? Has it done a decent relearn cycle? Is it burning oil? There’s lots of questions and emissions is a pain in the arse - just swapping stuff won’t necessarily help.

[jonwat]

1 hour ago, Barrykearley said:

You need that car on freescan or espritmon.

Didn't realise the V8 could be accessed by Freescan or Espritmon, thought it was OBDII??? 

[Bibs]

The car is a 91 SE, I've move this thread into the correct forum now. 

[Devilish]

The O2 sensor I'm using is a new Bosch (original O2 sensor, part number matches the original)

The car stutters at low RPM. Almost like it's missing. If it's in gear it's jerky (Like a kid learning to drive a manual transmission lol)

Checked the TPS and checked the Ohms, started at .4 and ran up to 4.4 without any dead spots, so it's good.

What is IAC? (Sorry I'm a little new to this.

How do I get it to do a relearn cycle?

It was burning oil as the crank case breather hose was blowing oil into my air filter, have since put a 3/4 catch can on it and it seems to be good.

My dipstick is never low on oil the entire time, so I don't think it burnt much of it.

 

Thanks a lot for the help so far, I appreciate it!

[Barrykearley]

The TPS needs to be set to about 0.6v on freescan - and you need to ensure that it shows 100% on the screen when throttle pedal buried and that the voltage increases as it should.

the Iac or aic - always get the the wrong way round - it’s an air bleed in valve on the fuel injection rail. These are GM units and were awful of the vectras and cavaliers they were used on in this country. They cause rough running and idle issues. What you describe above is fairly indicative of that part needing replacing.

a relearn can done by forcing a reset on freescan and/or removing power from the ecu and restarting the car and letting it run on idle until The fans cut in - it then needs about 30 miles of driving.

are all the inlet gaskets new? You don’t want a torn old one leaking air in

[Richard123]

Sounds like you got a bad cylinder.  Pull a plug at idle and see if one isn't contributing.  A dead cylinder will pass plenty of unburnt fuel.     

[Devilish]

Can I remove this air bleed valve or should I relieve pressure first? Never done this before.

Is it located on the front of the fuel rail or rear?

 

I've tested all the cylinders for spark, all the wires were also checked, new plugs put in as well. All pugs were burnt, not wet which tells me they're working...however they're all black not a nice brown colour.

[Richard123]

OK, so rich mixture on all 4 cylinders.  See the other thread in this section about fuel pressure regulator.  Pull the vacuum line off it and see if it stinks of fuel, internal diaphragm might have blown so it might be leaking raw fuel into the manifold.

 

  

[Devilish]

Awesome, I'll check that out!!

Thanks for the tip!

[Vanya]

What injectors are you using? 

I had some garbage from FiveO-Motorsports in my SE one year and couldn't pass emissions to save my life. It would pop and bang like crazy due to over fuelling, and the spec was "correct" on paper. Switched to original injectors, which I'd had cleaned in the meantime and hey presto, no more issues. And I'm running a sports cat as well.

Edit: with the aftermarket injectors my car would also jerk and stutter for no reason on occasion, usually when depressing the accelerator - it would stutter and then from out of nowhere just go full on hard acceleration. 

Edit 2: Despite what "experienced Esprit owners" might recommend, I've found it's best to use original parts where possible. Any time I've had my SE acting up, it's been due to aftermarket or "alternative" parts. 

Edited May 11, 2018 by Vanya

[Devilish]

I put in Five-O injectors. After I installed them they ran great, no issues at all, car had good response and ran like a dream.

After sitting in the garage all winter (heated garage) I took it out for the first few runs and it's acting up.

[Vulcan Grey]

I recently cleaned my injectors, after sitting for a year, with an $8 kit from ebay.

Like this

https://www.ebay.com/itm/Auto-Car-Vehicles-Tool-Universal-Fuel-Injector-Flush-Cleaner-Adapter-DIY-Kit-Set-/222347490799

It actually worked really well!

[Devilish]

What is this called exactly?

its on the end of the fuel rail, I believe it’s the fuel pressure regulator but can’t find a matching one to buy?!

[Barrykearley]

Yep that’s what it is

Sj Sportscars stock them

[Devilish]

Any idea where I can buy a new one?

mine is screwed, pumped up to 20 psi and it leaks to 15 within seconds

[Vulcan Grey]

JAE in California also has the fuel pressure regulator.

You might have a leak of the diaphragm in the regulator, but it could also be the fuel pump or pulsation damper being the cause of the pressure loss.

Something to keep in mind

 

[Devilish]

The pressure loss was when the regulator was removed and tested 

[Vanya]

Try switching back to your original injectors. I'll bet you'll pass emissions. My car also ran fine initially, with "good response" as you put it, but the same issues reared their head later on maybe a month after installation. Trust me. Only takes like 10 mins to switch the injectors anyway. 

Edited May 13, 2018 by Vanya

[Devilish]

So new fuel pressure regulator went in...it ran good for the first test drive, now the engine stumbles and has a misfire.

i can’t seem to win...also can’t find my original injectors to put in 🤦‍♂️

[Vanya]

On 24/05/2018 at 06:49, Devilish said:

So new fuel pressure regulator went in...it ran good for the first test drive, now the engine stumbles and has a misfire.

i can’t seem to win...also can’t find my original injectors to put in 🤦‍♂️

Just buy a new set, they cost peanuts last I checked.