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-   DIY Turbo Discussion (https://www.miataturbo.net/diy-turbo-discussion-14/)
-   -   Boost is good, Idle issues now. (https://www.miataturbo.net/diy-turbo-discussion-14/boost-good-idle-issues-now-36317/)

jcnsue 06-20-2009 09:49 AM

Boost is good, Idle issues now.
 
Ok, thanks for the help, I had the wrong fuel line plumbed to the vortech FMU. Switched and test drove. WHOA, boost is good. No pinging, boost arrives around 2800-3500 depending on load and gear. Was taking it fairly easy on it. Now, started fine cold but barely idled, like it had a cam in it, got better as it warmed up. I've reads about some idle adjustments, but not sure what and where. Can anyone clue me in. Getting beter, thanks.:laugh:

magnamx-5 06-20-2009 09:51 AM

Vaccuum leak for one. check your lines and other shit.

ThePass 06-20-2009 12:24 PM

turbo shouldn't effect your idle. vac leak maybe.

jcnsue 06-20-2009 05:03 PM

thanks, I got some open time tonight, double check all lines.

jcnsue 06-20-2009 06:58 PM

vacuum lines all seem good, capped em off and idle still eratic. shimmed the BOV with one more washer, didn't help, going to get plugs now. be back

jcnsue 06-20-2009 08:03 PM

plugs in, no different. runs rough at idle checked vacuum, have about 18in vacuum at good idle, drops anf flutters between 13-15 when running rough smelss rich out the back. Please help, got to get this going.
thanks

Savington 06-20-2009 08:12 PM

Fuel pump? Fill out your signature.

jcnsue 06-20-2009 08:47 PM

took the car out, seems to build boost fine and run ok out of idle. took off the air filter and reached in and played with the airflow valve, moved it a bit in and idle smoothed out. is ther any adjustments on that. I did the sig. thing, I think. thanks

magnamx-5 06-20-2009 09:15 PM

yes there is you can mess with the spring tension most people only do it when running larfer than stock injectors. So i am thinking your return line is partialy blocked at idle causeing the pressure to be to high and making you run like shit.

jcnsue 06-20-2009 10:08 PM

tHanks for the suggestion. Just took the car out, runs good, boost builds, no pingin, all seems to be well with that end of it. Coming to a stop, let off gas, idle comes down normally, smooth and all for about 5-8 seconds, then it starts to stumble put and putter, wild guess it seems to be loading up. taking of it light hesitation then runs up no problem. Coming to a stop and taking off while it still idles good(the first 5-7 seconds) takes off like normal. If the return line is blocked at all, wouldn't it have running issues off idle. Help

jobambo 06-20-2009 10:29 PM

Did you do a boost leak test or just looked at the lines?

94mx5red 06-20-2009 10:29 PM

Try turning your idle up with the screw in the throttle body.

jcnsue 06-21-2009 12:14 AM

OK, so I'm learning, can someone explain how to do a boost leak test. As far as the vacuum lines go, I capped them off one by one and nothing changed. The car ran perfectly before turbo install. Remember, I had the pressure line to the FMU the first time, thats when it wouldn't do anything past light throttle, could that have messed up something. Other than the idle it runs great. The only vacuum lines I messed with are the one I teed in to for the Vortech and the other is the capped one on top of the throttle body, which i teed into for the BOV and the JR timing retarder. I recapped the one and plugged the other, no change. Does the O2 have much to do with idle.

dustinb 06-21-2009 07:59 AM


Originally Posted by jcnsue (Post 421788)
OK, so I'm learning, can someone explain how to do a boost leak test. As far as the vacuum lines go, I capped them off one by one and nothing changed. The car ran perfectly before turbo install. Remember, I had the pressure line to the FMU the first time, thats when it wouldn't do anything past light throttle, could that have messed up something. Other than the idle it runs great. The only vacuum lines I messed with are the one I teed in to for the Vortech and the other is the capped one on top of the throttle body, which i teed into for the BOV and the JR timing retarder. I recapped the one and plugged the other, no change. Does the O2 have much to do with idle.

Which line did you T into for the Vortech? Also, yes, you need your oxygen sensor.

jcnsue 06-21-2009 10:57 AM

Teed into the line by the fuel regulator. thats where the Greddy instr. said to, my instr. are copied very badly, thats prob. why I reversed the fuel lines earlier. I know I need the O2 but what does its position in the DP have to do with anything. Too close??, too far?? Thanks again

jobambo 06-21-2009 05:26 PM

Proper Preparation Prevents Piss Poor Performance

Quite possibly the best basic guide on getting your car running properly. Just replace replace everything Z specs to Miata Specs.

jcnsue 06-21-2009 06:27 PM

WOW, thanks for the read, lots of good info there. I've got to do a couple of those. Question, what does the AFM have to do with idle, fuel pump, etc. I removed the air cleaner and while the engine was runninf rough and lightly pushed the flapper valve back, and I mean barely and the engine smoothed out idle and stayed there until I let go, then it roughed up again. Does the fuel pump shut off and on based on the valves position, and or could I have blown my regulator when I had the fuel lines reversed to the Vortech. That would have put the fuel pressure on the wrong side of the reg.? thanks again

jcnsue 06-22-2009 11:04 PM

HOW STUPID, Sometimes the most obvious are the most difficult to find. On the intake side of the turbo I have a bracket for the heat shield mounted to the upper threaded hole. Had test fit bracket and was off when all problems existed. DUH, didn't realize it was all the through into the turbo. BIG VACUUM leak. Amazing the difference when its all properly finished. Wow, thanks for all the help, learned a lot, time to have some fun.


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