Misfire caused by ITG Maxogen

[flatfour]

ALL,


OK, so it looks like the problem is not actually the intake, but instead a coincidental gathering of water inside the spark plug housing. How the heck did all of that water get in there?

Apologies for raising concerns over the intake....

Flat4

[rob13572468]

Originally Posted by flatfour

I have had my ITG Maxogen installed for two weeks now and thought all was OK. I have noticed an occasional missfire when switching onto the upper cam when the engine has really warmed up (85-90 Degrees).

The power totally goes an the car bogs down as opposed to picking up nicely. It doesn't always do this, but has done it several time repeatedly on one particular drive which caused the CEL light to come on. I had this reset by a dealer, he said to just keep an eye on things in case it happens again.

I will more that likely be removing the intake to save my engine.

All vacuum pipes have been removed as part of the installation (as normal), and the solenoid is blanked off as well as the manifold where the pipe from the solenoid used to go - all as per the ITG instructions. I have checked the MAF sensor for locatio, all is OK.

Has anyone else had this prblem apart from the guy who just said it went away.... problems don't do that for me.


ta,

Flat4

hmm strange... maybe lean misfire?... when it happens only occansionally it tends to become one of those difficult to pinpoint problems. did you check to make sure the MAF sensor wire is not dirty?

[DSal]

Agreed, sounds like a lean misfire. Have you had a chance to dyno the car with the maxogen on? It may have an indication of how rich you're runnin etc.

[Greg]

Originally Posted by rob13572468

hmm strange... maybe lean misfire?... when it happens only occansionally it tends to become one of those difficult to pinpoint problems. did you check to make sure the MAF sensor wire is not dirty?

Classic problem after installing oiled foam filter. So classic, K&N feels the need to respond:

http://www.knfilters.com/massair.htm

People still blame these (type) filters for screwing up MAF sensors. Perhaps it became dirty during installation, or you have some leaking duct-work.

Clean your filter, replace the MAF sensor, make sure you don't touch it. Make sure the duct-work is installed and there's no way for contamination. Change your plugs which are probably fouled by now. If it happens again, you might then revert to stock. Unfortunately, you might have to replace the MAF again. Once they are gone, they are gone, and they are expensive to replace for the measly 2hp gain you got from intake modification...

You might also revert to stock, wait for the misfire and the MIL, then take it to the dealer for MAF replacement under warranty. Unfortunately, if they know you modified the intake, you probably won't get warranty support for the MAF...

'Greg

[Jack]

Flatfour -- did the dealer tell you the CEL code? Was it the misfire code or the lean condition code?

[Jack]

Originally Posted by Greg

People still blame these (type) filters for screwing up MAF sensors. Perhaps it became dirty during installation, or you have some leaking duct-work.
'Greg

The Lotus tech can check whether the MAF is functioning properly once he's got the Lotus scan tool connected -- he probably did. I doubt his MAF is the problem. These cold air intakes may cause a lean condition CEL fault, as some have already reported.

[CALtd]

Installed the ITG Maxogen yesterday and took a 150 mi mountain road trip today (50% highway to get to the mountains). Not a hiccup in the sytem.

[Greg]

Originally Posted by Jack

The Lotus tech can check whether the MAF is functioning properly once he's got the Lotus scan tool connected -- he probably did. I doubt his MAF is the problem. These cold air intakes may cause a lean condition CEL fault, as some have already reported.

I'm sorry, but this is just not completely true. The computer can "check" for open or shorts but there is no way that it can tell if the sensor is calibrated correctly or dirty, or ruined by oil from the filter. To do this, you would have to pull the MAF and calibrate it with a known volume of air at a known flow. No way you can do this just by hooking up a scan tool.

How does this "lean" condition come about if the sensor is reporting the correct air flow? Assuming all other systems are working correctly, it cannot.

MAF sensors are wires exposed to the air flow. Current is applied to the wire to heat it up and a thermocouple measure the temperature of the wire. The amount of current required to keep the wire at a fixed temp is a function of the mass of air passing over the wire. The computer has a lookup table in memory and maps the current to the amount of air passing throught the control volume of the throttle body.

Dirty MAF sensors cause incorrect flow measurements and "lean" or "rich" air/fuel mixtures because the correct air mass is not being reported to the computer. High-flow filters also let more dirt by, in addition to more air.

Lean conditions would be intermittent at first, and probably progressively get worse. Clean or replace the MAF, and see if the misfires continue. If so, replace the stock intake, and clean the MAF again. If you still get misfires, take it to the dealer and make them replace the MAF under warranty.

'Greg

[Jack]

Greg, I'll defer to your superior knowledge. What I was trying to say was....the tech can monitor the MAF readings at various RPM's and determine if the MAF voltage readings are within spec and hence working properly. I agree that MAF sensors can routinely go bad on cars -- that has happened on some Porsche's I've owned -- but the tech could always diagnose that issue by studying the readout on his OBD computer, as well as the code for the CEL. For sure, studying the condition of the MAF by pulling it can also help with any diagnosis.

[Dro]

People without problems don't usually start threads to say so, so in the interest of balance I want to point out that many people have installed the ITG without any problems. I have 1500 miles on my ITG and the car runs great.

[Ground Loop]

Originally Posted by Greg

I'm sorry, but this is just not completely true. The computer can "check" for open or shorts but there is no way that it can tell if the sensor is calibrated correctly or dirty, or ruined by oil from the filter. To do this, you would have to pull the MAF and calibrate it with a known volume of air at a known flow. No way you can do this just by hooking up a scan tool.

By watching/graphing the MAF reading during a drive, you can get a pretty good idea of whether or not it's working correctly, especially if you have other cars to compare to.

The Scantool (or even a generic OBD tool) can show the current airflow reading in real-time, handy for finding out if you're hitting the limit of the sensor, or getting erratic readings.

The Lotus ECU will also trip an error (P0101) if the "range or performance" of the MAF is detected to be out of spec, though they don't say what that means.

TYpical values are 1.5-5.0g/sec (idle), 5.0-15.0 g/sec (2500 idle). That should be easy to confirm.

And I was surprised to see that we do indeed have a hotwire MAF. It should have plenty of available range to cover increased intake flow, right?

[flatfour]

Thanks for all of the replies. The fault was the "Missfire fault" causing damage to the catalyst. This was reset, and I drove thr car for 5 miles (thrashing) and no missfires were apparent. Then I got the car hot on a long run and the missfire returned. I will remove the Intake and see hoe the car does as standard. All pipework is tight and sound, the MAF sensor looks as clean as a whistle (looks).

I never had this grief wth a scooby - decat, ecu, etc. I am keen to see if all is safe wehn it is back to standard.

Flat4

[flatfour]

what does the remotely mounted valve do that is mounted on the ecu but blanked off for the ITG installation?

[Ground Loop]

Originally Posted by flatfour

what does the remotely mounted valve do that is mounted on the ecu but blanked off for the ITG installation?

Airbox Flap Valve?

Airbox Flap Valve
In order to reduce airflow restriction into the airbox at periods of high demand, and also to provide an
acoustic enhancement, the ECU, when switching to high valve lift mode, also opens a flap valve in the underside
of the airbox body. This butterfly valve is sprung open, and is closed by a vacuum actuator supplied from
the inlet manifold. The vacuum supply uses an in-line non-return valve and a reservoir incorporated into the
front face of the airbox body to maintain flap closure during periods of low inlet depression. A solenoid valve
mounted on top of the airbox, and connected into the vacuum capsule line, is energised by the ECU when appropriate
to ventilate the capsule and open the valve.

[flatfour]

Hmm.


I can try that, but the photo is the same as my installation and is from the ITG website.


ta,

Flat4

[Jack]

Originally Posted by flatfour

Hmm.


I can try that, but the photo is the same as my installation and is from the ITG website.


ta,

Flat4

Won't make any difference.

[Greg]

Misfires can be caused by other things and it just may be coincidental to the ITG install, so you may want to rule out the following (or make sure your technician has ruled out):

coil pack
ignition wires
plugs
fuel pressure regulator
fuel filter
knock sensors
vacum lines

I don't think I saw a vehicle history anywhere. How many miles are on your engine? Of course all the above is unlikely if you've only got 3k miles on your car, but just to be complete...

[qball]

Mine is working great. It is on top! I like it when she's on top! Ha!

[The Stig]

Originally Posted by flatfour

I have had my ITG Maxogen installed for two weeks now and thought all was OK. I have noticed an occasional missfire when switching onto the upper cam when the engine has really warmed up (85-90 Degrees).

The power totally goes an the car bogs down as opposed to picking up nicely. It doesn't always do this, but has done it several time repeatedly on one particular drive which caused the CEL light to come on. I had this reset by a dealer, he said to just keep an eye on things in case it happens again.

I will more that likely be removing the intake to save my engine.

All vacuum pipes have been removed as part of the installation (as normal), and the solenoid is blanked off as well as the manifold where the pipe from the solenoid used to go - all as per the ITG instructions. I have checked the MAF sensor for locatio, all is OK.

Has anyone else had this prblem apart from the guy who just said it went away.... problems don't do that for me.


ta,

Flat4

Just curious, did you buy the intake from Sector111? If so, and the product is defective, I am sure they would take it back or exchange it... they are pretty stand up people. Also who did the install on it? Was it your dealership or did you do it yourself?

Neil

[Modern Wedgie]

We noticed that you are located in England. Perhaps you should consider contacting ITG directly about these issues.

Let us know if anything develops. If any of our customers ever have similar issues, this way we may know how to resolve them.