Emissions failure: 94 540i

[945401A_SPORT]

print out says NO level too high; whats the problem?
FYI, I have a conforti chip. Could this cause the failure? If so, I still have the old chip to put back in. Car is OBD 1.

if there were vacuum leaks, check engine light would come on?
139000, but was replaced by original owner, so probably about 80000 (NIKISIL to ALUSIL).

koalamotorsports.com told me of potential intake gasket issue. stealer told me that carbon build up is possibly the cause. he suggested to add a fuel additive, use 92 octane next fill up, and add the same additive, that may solve the problem. car was at normal op. temp today when failed.
inspection light came on earlier this week, but stealer said not an issue.

[zman-95-540i]

I would try the high octane fuel with a techron additive to see if that helps. That happened to me on an e36 I used to have and the techron solved the problem.

[945401A_SPORT]

techron additive? any specific name brand you used?
also, i was told by someone that you can use two additives, and that will work faster?

lemme see, can you say burned out injectors...?


I would try the high octane fuel with a techron additive to see if that helps. That happened to me on an e36 I used to have and the techron solved the problem.

[Bill R.]

couple of tanks of gas. Yes, a conforti chip or any chip for that matter will contribute to a failure from NOX.

Simply put , high performance engine generate more nox due to high combustion chamber temperatures. EGR valves are used on many cars to lower these combustion chamber temps (CCT) They do so by diluting the cylinder charge with already burnt gas which reduces cct and lowers nox.

A chip advances timing as much as possible which is where a lot of the performance gain comes from. Advanced timing raises Nox.

Carbon deposits can also raise nox if they raise the compression ratio. A techron or other combustion chamber cleaner can help IF you have enough buildup to raise your compression,(not likely) But by all means run some through. I would also go back to the stock chip for now and run some gas thats at least 10% ethanol in the tank when you go for emissions. That will also lower NOX by reducing cct. You catalytic converter is a 3 way cat meaing it also lowers nox when working correctly so make sure that the cat is warmed up completely, keep the engine running while waiting in line so that the cat stays hot and go on a fairly long drive before going to emissions with the engine rpm above 2500 to help heat the cat up.





print out says NO level too high; whats the problem?
FYI, I have a conforti chip. Could this cause the failure? If so, I still have the old chip to put back in. Car is OBD 1.

if there were vacuum leaks, check engine light would come on?
139000, but was replaced by original owner, so probably about 80000 (NIKISIL to ALUSIL).

koalamotorsports.com told me of potential intake gasket issue. stealer told me that carbon build up is possibly the cause. he suggested to add a fuel additive, use 92 octane next fill up, and add the same additive, that may solve the problem. car was at normal op. temp today when failed.
inspection light came on earlier this week, but stealer said not an issue.