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I failed the 2500 RPM CO (%) by a good amount. Max is 1.00, Gross Polluter is 2.50. I measured in at 3.56
I barely passed 2500 RPM HC (PPM). Max is 140. Gross Polluter is 290. I measured in at 132.
I'm still figuring out the car. The air filter is clean, it appears to have stock injectors. I may open up the computer and look for a performance chip (I'm not sure what to look for yet). The turbo looks stock and drives like a dream. No oil leaks. No coolant leaks. She has a black manual boost controller and according to receipts a turbonetics wastegate. My hunch is she's stock minus the manual boost controller and waste gate. Around 180,000 miles and I suspect has a history of being raced.
I'm guessing it's the catalytic converter.
thoughts? anybody have a spare catalytic converter to rent out?
I am scheduled for a diagnosis at the smog place to try and identify what is going on.
Last edited by Chapman951; 09-11-2019 at 06:20 PM.
If the car has a manual boost controller, I suspect it has an aftermarket chip. Open up the DME and post a picture of the chip.
Some of the item that affects AFRs:
- Fuel pressure Regulator. Stock chip requires a 2.5bar FPR. Aftermarket chips may use 3.0bar or the 2.5bar. Basically the DME chip dictates which FPR is required.
- Injectors must match the chip's configuration.
- Engine Temp sensor. If it reads cold, the the DME adds fuel.
- Bad O2 sensor. If it's reporting "lean" the DME will try to compensate by adding fuel (closed loop)
- An out of adjustment AFM. If someone messed with the AFM or it has a bad spot, it could send the wrong voltage to the DME causing rich AFRs.
- Fauly TPS. If it's reading WOT instead of PT, the WOT maps are rich...
- obviously, the DME chip will have the commended AFRs.
Clark's Garage is a good resource to get details on how to check the above.
As a rule, prior to the emission test, run the car at highway speed for about 30min. Do not shut it off prior to the test (you want the cat to stay hot).
Thank for you help. Will report back what I find.
Happen to know if disconnecting the stock AFM connecter with the battery still connected and then reconnecting the AFM connector will cause boost to stop working? My car will now only get to 5psi boost instead of 14psi.
Disconnecting and reconnecting AFM should not affect boost.
Since you have an MBC for boost control, check it first. At least make sure the MBC is being used and not the KLR+Cycling valve. If MBC is in control you can adjust it.
I strongly recommend getting a boost gauge if you are using an MBC. You want accurate boost. Factory boost gauge is not very accurate.
Originally Posted by Chapman951
Thank for you help. Will report back what I find.
Happen to know if disconnecting the stock AFM connecter with the battery still connected and then reconnecting the AFM connector will cause boost to stop working? My car will now only get to 5psi boost instead of 14psi.
It does indeed have a performance chip. From AUTOTHORITY.
To fallow up on your other comments:
- Fuel pressure Regulator <---- I will research this tomorrow - Injectors must match the chip's configuration <---- they look stock, but I have no clue what is stock and what is not. - Engine Temp sensor <---- the engine temperature gauge in the dashboard works. It moves up and down. - Bad O2 sensor. If it's reporting "lean" the DME will try to compensate by adding fuel (closed loop) <--- I have an aftermarket air:fuel meter installed which is constantly in the center position (picture attached)
- An out of adjustment AFM. <--- The car is driving fine. I don't notice anything. - Fauly TPS <--- I will research this tomorrow
Thanks very much for your help! Pictures attached below.
I will take your advice about running the car for 30 minutes prior.
I've attached some images.
AutoThority Chip After market Air-fuel Monitor Boost Gauge and MBC Professional MBC install injector pic injector pic 2 injector pic 3
Well you can change anything but until you determine what chip is it, you won't know anything?? And if it passed at idle that is at 14.7 afr.. But 2500 rpm load, I don't think boost would be a factory?? On my chipped car, I think it passed with the chip at 17 psi and the 55 injectors installed on it but the cat was back in place.
In any case if you have a MBC, you "need" a boost gauge and a wide band sensor O2 sensor would be "helpful." Then you would be able to see the AFR at "2500" rpm. I use to be a smog tech in CA back in the day ... . and if you'd have come to me, you'd have passed! That's kinda why I quit that job.
What state are you in?? If 2500 is close to 14.7 or lean, in any case, a cat would most like solve your issue??
AUTOTHORITY. ... that is a very old chip. And most likely that is also a narrow band band sensor ?? Reads only to 1 volt, so it can't read open loop?? I think but I have been out of the game for awhile and now I'm living in rural NV, they don't care and neither do I! ..
Have you taken care of the basics? When was the last time you did an oil change, changed spark plugs, changed the cap and rotor, replaced the air filter, etc.? Last time I had my car smogged, it failed with high hydrocarbons and carbon monoxide - I did the above maintenance, changed the o2 sensor, and ran some Seafoam through the fuel system. Got the cat nice and hot, went for a retest, and it passed just fine...
One last thing - have you checked your FQS setting? Maybe you can set it to a leaner setting...
3 1/2% CO is mighty damn rich at a 2500 RPM cruise. I'd expect between 1- 1 1/2, without the cat. Through a functioning cat, not uncommon to see zero.
The AFR monitor you have looks pretty ancient, if it was accurate it would be pretty much pegged rich at that mixture.
Haven't needed to smog one lately... but even with an Autothority chip my low mile 951 sailed through below 1% without the cat.
'Fast951' is spot on with his recommendations. Words of truth!
Good luck!
@2500, CO is way too rich and there is no oxygen left over for your cat to react and clean the combustion gases. If you havent already, just swap in a new 02 sensor and see if you get any significant changes in the end result; otherwise, If the cat is original, I suspect your cat has lost it's efficiency due to the oxygen levels on the failed 2500 rpm test regardless of your mods,
Thank you everybody for the support.
I have just spoken to a Porsche technician and immediately noticed the AFM screw was WAY to deep. He recommended unscrewing it 2 full rotations and going again for a pre-smog inspection. This is one of fast951's suggestions to look at too. My air:fuel gauge steadily reads 14.7. It is the red light on the monitor pictured above.
fast951 - I'll keeping my fingers crossed the AFM screw is the problem. Jim O. - I know oil was changed less than 500 miles ago and the air filter looks brand new. Everything else looks new but i'm not certain. Nowanker - Thanks for posting! Your comment makes me lean even more towards the AFM causing the problem. If I need to dive deeper, I will research FQS kev951 - O2 sensor might be next on the list
My appointment is Friday 9AM (pacific coast time)
If this does not work, I will continue diagnosis.
It's been a seriously long time since I delved into early Motronics...
But from memory, the screw on the AFM is just an air bypass, which would have a lot more effect at idle than at cruise. Easy to imagine that the AFM is jacked, or that someone diddled it!
Also from memory... when you ground the O2 sensor lead, it throws the mixture rich. If the sensor or harness are shorted, same result?
As for that aftermarket mixture gauge... Again, from memory, AFR of 14.7 works out to somewhere around .7% CO? (that's point 7%). There's no way that gauge is accurate against a measured 3 1/2% CO.
Other thoughts... the DME temp sender isn't the same one as the gauge. Forget exactly which way they go, but it's either open circuit or shorted, (think it's open) it'll read stone cold and richen up accordingly.
But if my memory is off, someone please refresh it!
You mentioned the AFR display is stuck in the middle. This raises a red flag.
- The gauge may be faulty/bad. If the injectors duty cycle is working, then I would investigate further (see next).
- Make sure the AFR display is actually connected to the O2 signal wire. I may have the instructions for this particular display if you need to know the wires designation.
If not connected, then make the proper connection.
- If the display is wired correctly, and display remains stuck in the middle, the O2 sensor may be bad. Verify it is connected to the DME harness (plug by oil filler tube, back of intake).
With a working O2 sensor. I expect the AFRs to dither back and fourth (closed loop). Unless it's off the scale rich or lean where the DME cannot control it. But your idle is fine, so it should ditger. Once you get the AFRs dithering, you can lean out the mixture via the FQS (if needed).
Most APE chips used stock 2.5bar FPR. Verify you have the correct FPR, the pressure is engraved on it.
And as a last resort, you can always add E85 to the pump gas. This will automatically lean it across the board. E85 requires 25-35% more fuel by volume than pump gas to get the same AFRs. So by adding E85 without increasing fuel delivery, you will lean out the mixture.
WARNING - stay off boost as lean mixture will hurt your engine.
You can calculate the E% of the fuel mix in the tank (based on the ratio of gallons of pump vs. E85) . Once you have the E%, you can calculate how lean the mixture is going to be. Simple math. This will be affect AFRs across the RPM range.
The person diagnosing the smog failure recommended me to a European car specialist to sort out the vacuum lines. He had no idea what was going on. From my understanding and talking to everyone, my car is experiencing a RICH condition.
He did state the fallowing though:
1. The catalytic converter looks brand new
2. When he put his finger over this brake booster line, the car would run much worse
To sum up everything SMOG related: Air intake filter: Looks brand new Catalytic converter - was told it looks brand new by smog technicial TPS - i'm not experiencing the idle symptoms described on clarks-garage.com Fuel Pressure Regulator - is a bosch system that says "made in Germany" i'm not experiencing the idle symptoms described on clarks-garage.com. i'm under the impression it's 2.5 bar unit. Injectors - appear stock oil change - performed last 500 miles
suspects: AFM - The allen bolt could still be far too low. I rotated it counter clock wise twice. Injectors - poor spray pattern O2 sensor - It does not have the symptoms as described on pelican-parts.com, but while i'm inspecting the waste gate tomorrow as my possible culprit for no boost, I will look at the o2 sensor. A poor o2 sensor might be why my Air:Fuel monitor is not moving around that much. I did see the air:fuel monitor move 1 light over to the lean side. (https://www.pelicanparts.com/techart...eplacement.htm) fast951 - I was able to see the 02 sensor connected behind the intake manifold. fast951 - if you have those instructions, that would be awesome. FQS - Is there a correct setting for this on the KLR? I know it's a (-2 -1 0 +1 +2) set-up. Thanks Greg for that! Chip on DME - It is running an AutoThority chip spark plugs, distributor, - unknown age Engine Temp sensor - I still need to figure this one out
I think that covers everything SMOG related :-)
I might end up going the E85 route. I'll keep diagnosing for a bit. The SMOG tech said I could swing by for a quick snuff while diagnosing the car.
Pictures! The snorkel for air box is installed.