SCCAIT7

Hello gentlemen -

I am bringing the Turbo II out of the barn ... I went to get the emissions done after driving it about 45 minutes before. Since I got it running (out of the barn) I have only put about 25 miles on it ...

On the 25/25 test she failed on HC's with a reading of 431 and CO% 4.72

On the 50/15 it passed with a reading of 97 and 0.27 -- I really dont understand this because its more of a load - It would seem like it would fail on this one not the "light load" test ...

Also the engine is idleing at about 1500 and bounces between 1500-1600 ... Up and down up and down ... Any ideas?

RotaryRocket88

iTrader: (7)

That CO% is very high. I'd make sure the air pump/air injection is working correctly and inspect/replace the main cat.

A bouncy idle can be due to the TPS needing an adjustment.

SCCAIT7

Thanks Rotary - After some investigation - The hose that goes from the air pump to the air filter housing is none existant. I made another hose this evening. Also pulled the plugs and checked them.

I also think I made a fatal mistake in that I let the car idle for 10-15 minutes waiting in line for my test - My theory is this allowed the engine to load up on fuel ...RICH... thus why on the second test the numbers dropped dramatically.

I am going to search for TPS adjustment rather than asking ... unless you have instructions easily handy!

j9fd3s

iTrader: (3)

the TPS adjustment is in the shop manual, foxed.ca

if you have WORKING air injection, letting the car idle is good, as the cat gets hot, and they work better when they are hot. what you don't want to do is turn it off. its very common for the Air Control Valve to be bad, or have the vacuum lines crossed

SCCAIT7

J9 - Shame on me ... I do not have a shop manual.

This evening I went searching for the TPS. . . On the radiator side of the intake I see a black sensor with a "button" that us up against the throtle (looks like a TPS) ... However I do see an adjustment - It just has two 10mm bolts holding it.

jackhild59

iTrader: (7)

Sure you do. It was given to you in the previous post. You just have to pay attention to little details.

http://foxed.ca/foxed/index.php?page=rx7manual

SCCAIT7

My mistake - I didnt realize what fox.ca was ... Thank you.

I just did the adjustment and it did not make any difference. I was able to get it within spec. I am still getting a bounce that is going between 1500 - 1600. I disconnected the TPS and started the engine and it stayed at 2k rpm and did not drop ... I am wondering if after years of sitting if the TPS is bad.

jackhild59

iTrader: (7)

You are welcome! TPS adjustment works best for me using the two led light method. Try that.

Search for a thread that explains how to make the tester. Don't forget to jump the initial set connector.

Good luck!

jackhild59

iTrader: (7)

https://www.rx7club.com/2nd-generation-specific-1986-1992-17/emission-testing-texas-style-465422/

SCCAIT7

Well - I seem to have corrected the idle bounce ... I did a coolant flush this afternoon and the idle is is about 900rpm. The coolant that was in at was nasty ... I imagine one (or more) of the senors were not able to get the coolant temp to the computer.

Bravely - I took the car for another Emissions test and it failed even worse ... I had the car on the lift this afternoon also and I am not getting much of a temperature change after the cats ... I imagine they are shot ... Thats Monday...

Ill keep everyone posted. Thank you for your continued support! Slowly but surely we will have another Turbo S4 on the road ( Legally!!!)

j9fd3s

iTrader: (3)

before you replace the cats check the air injection, and the air control valve. if those are not working properly, then emissions will be high no matter what

jackhild59

iTrader: (7)

Post up the numbers for for CO, O2, NOx, HC from your test. That will help us help you.

SCCAIT7

Jack - I am going to try and make this as easy to read as I can ...

For the 25/25 test

HC ppm - 464
CO% - 5.38
NoXppm- 86
CO+Co2% - 16.2
RPM - 2938

For the 50/15 Test

HCppm - 412
CO% - 4.97
NoXppm- 89
CO-Co2- 16.1
RPM - 3000

Obviously the car is running very rich ... with the HC's so high

J9 - I was looking through the FSM on Fox.ca - I see where it says to test specific things - However I have to admit - I can certainly perform the tests - However I am not sure what it would mean or exactly what it would need to fix if something were wrong.

Could you perhaps give me a couple things to check and I can report back?

jackhild59

iTrader: (7)

Your cat is shot. Look at the excess CO number. If your cat was working but was being overrun by the rich condition, the CO would be non existent.

I bet the O2 number is high as well.


New cat is in store for you if you want to pass emissions.

SCCAIT7

Thats what I thought. When the car was up on the lift yesterday I looked at the temperatures going in and coming out ... from what I understand you want to see at least a 10% increase on the back side of the cat ... I maybe had 5 degrees.

Thanks for the confirmation. Fortinutly, I have a friend who owns a muffler shop...

SCCAIT7

New cat and two cherry bombs out back ... Car sounds awesome and passed emissions!

HC's dropped literally to like 15! Co2 % was like 0.04!

Thanks guys! Case Closed!