Exige V6 Air Intake System

[PJ 85]

Thanks, how did you notice this (while driving)?

These codes probably only show when the obd2 was read. 

[notabene 11]

4 minutes ago, PJ said:

Thanks, how did you notice this (while driving)?

These codes probably only show when the obd2 was read. 

I cant rev over 5500rpm.. 😥

[alias23 1,535]

@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).

[PJ 85]

Ah, thanks guys. No Imran, my car isn't showing any issues and happy with the Air intake system! 

[DrTroy 6]

Ah, I have this problem too, not rev past 5500, have to clear the codes via a scanner

[alias23 1,535]

If anyone’s having a problem ping me a mail and I’ll get you the replacement filter type sent out which should fix the problem 

[MARTIN_S 115]

Mine was fitted and I did the full run in procedure exactly as defined but, quickly got the mentioned error codes,  left bank or right bank running lean. Car then gets limited to 5500 revs max.

I could clear it with my obd, but the problem needed to be sorted fast and it was , with Alias dealing with the problem very quickly, after some decent research on the subject. I was sent a new air filter to fit that week, which has the same area overall area but 'might' be slightly more restrictive. Personally I think its a looks and feels better quality the foam ITG.

The end result was slightly less angry sounding than the ITG but, it still sounds pretty damn good and sound less 'breathy and sucky' than the ITG did. Hard to tell if it lost any power over the ITG but is still without doubt notably better than the original by a long way.

I've now done over a 2000 miles or more with this, including a track day and its been absolutely fine in summer and winter conditions.

Martin S

Edited March 6, 2020 by MARTIN_S

[zaero 3]

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 April 3, 2020 by zaero

[RoflOnMyWaffle 326]

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) ?

 

[alias23 1,535]

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). 

[dixie v6 50]

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...

[alias23 1,535]

Thats a worthwhile point @dixie v6 makes and may be an idea for you to test @zaero especially given your setup with the headers.

[notabene 11]

where did you guys get air straightener? 

[zaero 3]

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.

 

[zaero 3]

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

[alias23 1,535]

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

[dixie v6 50]

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...

[zaero 3]

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 ?

Edited April 3, 2020 by zaero

[alias23 1,535]

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 👍

[dixie v6 50]

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.....

 

 

 

[Kristof Thys 197]

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"...

 

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:

 

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 April 4, 2020 by Kristof Thys

[zaero 3]

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 April 14, 2020 by zaero

[alias23 1,535]

@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.

[Jack 547]

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.

 

 

[Kristof Thys 197]

Thanks for the info Jack; very  useful, you are a pioneer in the Lotus community thanks for that.  

it's a shame that Lotus didn't come back to us when I mailed the same conclusions on the carbon air intake (I shouldn't have used LinkedIn for that :-)).  But then a Cup R with its carbon intake isn't really built for every day traffic and the kangarooing we have experienced happens at low & partial throttle, low RPM conditions.  Also interesting to see that your AFRs at WOT seem to be less rich than what we see; might be down the the sensor (I use a Bosch 4.9 LSU) or does a CupR have another map compared to a road going Exige? (I have no clue)

Good that the AFRs look ok, so probably your short term fuel trims are not spiking as they did when we also had on two cars an alu intake tube without air straigthener at partial throttle and to a lesser extend at WOT near redline.

I am not being negative to any product here, I have no commercial intend whatsoever, I am only stating what I personally and Dixie with me have experienced since 2013 with the air intakes (that is the Lotus one, Dixie's first version in alu without air straightener and then both mine and Dixie's when we added the air straightener: STFT's much more stable and AFRs)

And judging by the PMs I've got last few weeks, the issue I describe above is no exception.  For the 2 euro's or so that that air straightener costs, and the fact that turbulent vs laminar air stream in any air intake where the ECU only relies on a MAF to get the mixture right is well documented, it gives me peace of mind that I am running one.

 

Edited April 19, 2020 by Kristof Thys