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As I own a 350 Sport and live only 20 mins away, Imran kindly offered to fit my intake for me so that he could familiarize himself with any nuances of the 350 compared to the V6S. The actual availabil

A few folks have been following my build thread for a while now, and in particular my efforts to design an air intake for the Exige V6. Given the amount of time, energy, trial, error, and results from

Today’s been a good day    

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@PJ you would get an EML light, then OBD would provide the detail of the error, if you dont have an EML you dont have a problem.

This is a minority problem which seems to only effect a very small number of people (6 out of 80) who seem to have a specific map that doesn't like the ITG so the recommendation is to change the filter (which I supply free of charge in these situations).

www.alias23.com

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  • 4 weeks later...

Guys, 

I'm also experiencing some issues after fitting the intake where the car will not idle when cold and accelerator input is inconsistent, ,aka flat spot. Im getting ECU codes checked next week and will keep you posted.

FYI - my V6 has headers and and 3" exhaust, everything was fine prior fitting the intake cause still TBD.

Edited by zaero
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1 hour ago, zaero said:

Guys, 

I'm also experiencing some issues after fitting the intake where the car will not idle when cold and accelerator input is inconsistent, ,aka flat spot. Im getting ECU codes checked next week and will keep you posted.

FYI - my V6 has headers and and 3" exhaust, everything was fine prior fitting the intake cause still TBD.

Im sorry to say but its likely due to you having headers and no cats as you may have pushed the standard ECU too far.... that said others have done this and its been fine. However its not something I have tested or marketed as being recommended. The intake is designed as a simple bolt on kit for standard cars (standard being standard engine). 

www.alias23.com

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I also have headers and no cats, (same as  Kristof) I have no problems with my intake that's almost the same as Imran's intake with the only difference that I added an air straightener before the maf , I did some testing with an air fuel gauge and without the air straightener air fuel ratio was very unstable...

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3 hours ago, RoflOnMyWaffle said:

Not being rude, just asking, but did you let the car idle for a solid 10-15 minutes before driving? Then drive at varying speeds and loads for 30 mins (not WOT) ?

 

No need to apologise Mike, it is a valid question. 

Yes, I'm aware that when the ECU is reset it needs time to re-learn the idle. This process needs to take place and idle can be high or hunting for the initial 15-20mins or so. However the throttle response is still normal during the learning process, in my case it is not, some times it will not accelerate at all or not rev past 3000rpm. 

Imran, nothing on your marketing or testing however it should be noted so that people are aware of potential issues. As I said the cause is still to be determined and I will post error codes and cause once confirmed. 

Perhaps similar to the 5000rpm issue that you did not experience during your testing as mentioned is previous posts. 

If air straightener is the solution it may be worth while to consider including in the kit (imagine it is a honeycomb piece inside the intake pipe ? @dixie v6, happy to test if you can provide more information.

 

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2 hours ago, alias23 said:

Im sorry to say but its likely due to you having headers and no cats as you may have pushed the standard ECU too far.... that said others have done this and its been fine. However its not something I have tested or marketed as being recommended. The intake is designed as a simple bolt on kit for standard cars (standard being standard engine). 

Imran,

I do have still have a cat, it is just further down the line where the 3rd Evora cat is in the US version. Engine is also standard for now ;)

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1 hour ago, notabene said:

where did you guys get air straightener? 

I bought it on ebay https://www.ebay.co.uk/itm/2-75-OD-x-5-Airflow-Straightener-Screen-187-honeycomb-cell-mass-air-flow/253004432030

I first made an intake without the air straightener (picture) but when testing air fuel was going crazy , when I added the air staightener air fuel was very stable ,been driving it for 4 years now without any problems...

PICT0494 (Middel).JPG

$_12 (Middel).JPG

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1 hour ago, alias23 said:

@zaero fair point - Ill update the product description to reflect the point ref headers etc... What headers are you using out of interest?

Exhaust and headers are from Simply Sports Cars here in Sydney. Just wait till I get them to check the car over, I'd like to know the root cause of issue.

Thanks for the link Dirk, do you track your Exige ?

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30 minutes ago, zaero said:

Exhaust and headers are from Simply Sports Cars here in Sydney. Just wait till I get them to check the car over, I'd like to know the root cause of issue.

Thanks for the link Dirk, do you track your Exige ?

The SSC guys are pretty good so you're in good hands :) They should also be able to help with the remap if needed as I believe they've got access 👍

www.alias23.com

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44 minutes ago, zaero said:

Exhaust and headers are from Simply Sports Cars here in Sydney. Just wait till I get them to check the car over, I'd like to know the root cause of issue.

Thanks for the link Dirk, do you track your Exige ?

No I don't track the Exige , I have a Renault Megane RS for track use , very cheap to maintain and very reliable.....

 

 

 

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Mind you that the carbon Lotus Motorsport CAI as on the CupR's doesn't have an air straightener neither.  When we measure the AFR's over the full rpm band, they where all over the place at the lower rpm's and at WOT, due to turbulent air flowing over the MAF sensor.  However, the HKS filter chassis has some "channeling" for the air, slightly decreasing the turbulence and this is why, albeit unstable, the short term fuel trims didn't go out of spec, hence not throwing a code.  Now, I personally wouldn't call that HKS thing "a filter"...

cai_lms1.jpg

cai_lms2.jpg

cai_lms3.jpg

 

However, with the more generic air filters, foam, oiled paper etc, you do get this turbulence, and incorrect air flow reading. The ECU tries to compensate for a lean situation and once in a while STFT go over +25% , throwing a P017x "system too lean".  In fact, they are spiking in both ways, lean and rich.  Most of the time you won't notice, but the ECU is constantly compensating for erratic readings which can result in "kangarooing" at lower rpms, erratic throttle respons and unstable idle (even more so at colder temps) and (albeit it exceptional) misfires in the high rpm band.

 

Two ways around this: get a more restrictive air filter, but that robs power or, and this is the only correct way, get the turbulence eliminated.  You do so correctly only with an air straightener.  Some companies install a tab just in front of the MAF sensor, keeping it out of the turbulent path, but this gives false reading, leaning out the mixture (and that is exactly where the extra power is coming from).

Air straightener in front of the MAF sensor, BMC oiled filter:

cai_as1.jpg

cai_as2.jpg

 

Don't take my word on it, just install a wide band O2 sensor pre cat any you'll see what I am rambling about (or read out your short term fuel trims for both banks over OBD)... or Mr. Google on "air straightener cai" for many many hours of nice reading.

The OEM airbox also has a (plastic) air straightener incorporated.

 

Easy fix, just make sure the air straightener is well fixed so it doesn't get sucked in the engine 😀

Edited by Kristof Thys
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  • 2 weeks later...
On 04/04/2020 at 00:57, alias23 said:

The SSC guys are pretty good so you're in good hands :) They should also be able to help with the remap if needed as I believe they've got access 👍

Just an update on the reported idle learning issues. I could not get the car to SSC as it kept throwing the engine light and went into limp mode a couple of times.

So I decided to look into the issue myself. first port of call was to check ECU error codes. This is what my ODBII reader showed me.

P2119 Throttle Actuator Control Range/PErformance

P2135 Throttle Pedal Position Voltage Correlation

P2104 Throttle Actuator - Forced Idle

P2106 Throttle Actuator - Forced Limited Power.

At first glance it was pretty obvious there was an issue with the throttle body, and P2119 and P2104 is common when there are issues with the MAF sensor/wiring. I had already done the obligatory MAF plug cable tie fix as per the service bulletin so I decided to pull the the entire intake out to check and clean everything.

Throttle body was full of oil from the breather hose, a surprising amount and so was the flex pipe. The MAF sensor was clean and both TB and MAF plugs were clean and still tight. I checked the flex pipe while cleaning it and noticed the breather hose fitting was quite loose, I could move the metal fitting in and out of the flex pipe to the point where air could enter thru the gap formed. Initial thought was that if air is getting into the intake after the MAF this would cause TPS or MAF errors.  

After cleaning the throttle body, the MAF sensor and both the plugs with contact cleaner and conditioner I put everything back together including the cable tie fix on the MAF and replaced the factory flex pipe with Imran's silicone one.

I then reset the codes and disconnected the battery for 30mins. Restarted the car and no engine light, idle although in learn mode was fine and no flat spot on acceleration.......EXCELLENT ....... Left idle to learn for 20mins and took the car for long drive on some of the best winding roads Sydney has to offer. Car was great ran like a champ without any issues for 3 hours with multiple stops.

I suspect there was a combination of things that caused the issues/error codes, but the flex pipe breather fitting where air was getting in was most likely the cause of the idle problem.

 

 

 

Edited by zaero
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@zaero good to hear you got to the bottom of the problem. Im assuming you're happy with the air intake system? Would be good to get some feedback on the intake and manifold setup you have esp as you've not had a remap. Be good to hear.

www.alias23.com

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On 04/04/2020 at 02:55, Kristof Thys said:

Don't take my word on it, just install a wide band O2 sensor pre cat any you'll see what I am rambling about (or read out your short term fuel trims for both banks over OBD)

Kristof, I did have a wide band O2 sensor installed on my CupR and have been logging A/F ratios since 2015.....very helpful in highlighting potential lean issues before causing engine damage. I highly recommend that "mod".

As a result, with some help from Lotus, we discovered early on in 2015 that the carbon MAF tube was causing a lean condition.  We installed an aluminum tube (without an air straightener) and changed out the HKS filter to a ITG filter --  subsequent testing showed good A/F ratios.  Turned out that the carbon tube, while smooth on the outside has by its nature a very rough, uneven internal structure and that, indeed, was causing the A/F problem.  I'm sure we've all heard the saying ... "lean is mean, until it's not".  ;) 

As an aside, we also found out (from reliable factory sources who shall remain unnamed) that originally when Lotus was doing initial tuning on the CupR, they were using an aluminum MAF tube w/o straightener and all was good.  The change to a carbon MAF tube was a "marketing" decision and no testing was done which would have revealed the unintended AFR consequences.... after all, carbon looks cool....crazy I know.

If interested, you can see my A/F numbers (as well as post-blower IATs) on the attached video...look for the AFRs when the car is at full throttle throughout the RPM range in various gears .... you will have to be the judge on the whether the AFRs are OK.  For reference, I do run unleaded 100 octane fuel and currently have 12,000 track/racing miles on the car, virtually all with the intake shown below which is very similar to Imran's, FWIW.

 

 

larger ITG installed.JPG

Jack
2008 2-Eleven
2015 Exige V6 CupR
Track videos ... http://www.youtube.com/jackcup
2010 Lotus Challenge Series ULTRA Class champion
2012 Lotus CUP USA OPEN Class champion

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