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Old 08-17-2012, 07:09 PM   #21
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You didnt floor it after installing all the new extras?
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Old 08-17-2012, 07:13 PM   #22
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Nope

After installing the new parts i turned it on and it was acting like this before installig the parts it was working fine just needed a new turbo because it had shaft play thats y i dont understand how i could have nuked it

Last edited by curly; 08-17-2012 at 09:40 PM.
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Old 08-17-2012, 09:15 PM   #23
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The obly thing i can think of that i changed that can make my car act like that is my o2 sensor i had a spare o2 sensor and i cut it and made it longer inorder to reach the downpipe maybe thats my problem??
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Old 08-17-2012, 09:18 PM   #24
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Your car is still running the stock air flow meter right? Check for vacuum leaks between the throttle body and the turbo.
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Old 08-17-2012, 09:37 PM   #25
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Yea thats right. Ill do that. I have an rx7 adjustable afm would that help??? Make itleaner or richer?
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Old 08-17-2012, 09:45 PM   #26
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No that won't help. The only thing the RX-7 AFM does is make the AFM opening larger, therefore giving you a little hp in higher RPMs, where the stock AFM chokes off your air a little.

Either one is "adjustable". If you take a knife and cut through the glue and take the top plastic panel off, you can adjust the clock spring stiffness. The stiffer it is, the less the flapper door is open, and I think the leaner it runs, and vise versa.

Do yourself a huge favor and mark where it is immediately after opening it, so you can go back if it doesn't help.

With your wideband installed, adjust the clock spring for a 14.7 idle. If you're still not getting a smooth idle, you've got another issue, but it's a good place to start.

P.S. This is for idle ONLY. The flapper is almost imminently opened with any amount of throttle, and no longer plays a roll in the fueling.

P.P.S. This isn't instant messenger, if you have more than one thought, put them all in one post, not multiple.
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Old 08-17-2012, 09:56 PM   #27
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Ok im going to try that as soon as my wideband is in
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Old 08-18-2012, 10:59 AM   #28
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Quote:
Originally Posted by curly View Post
No that won't help. The only thing the RX-7 AFM does is make the AFM opening larger, therefore giving you a little hp in higher RPMs, where the stock AFM chokes off your air a little.

Either one is "adjustable". If you take a knife and cut through the glue and take the top plastic panel off, you can adjust the clock spring stiffness. The stiffer it is, the less the flapper door is open, and I think the leaner it runs, and vise versa.

Do yourself a huge favor and mark where it is immediately after opening it, so you can go back if it doesn't help.

With your wideband installed, adjust the clock spring for a 14.7 idle. If you're still not getting a smooth idle, you've got another issue, but it's a good place to start.

P.S. This is for idle ONLY. The flapper is almost imminently opened with any amount of throttle, and no longer plays a roll in the fueling.

P.P.S. This isn't instant messenger, if you have more than one thought, put them all in one post, not multiple.
Actually "tuning" the VAF spring can be used for more than idle.

HOWEVER, i have a very big issue with tuning this way. By tightening the spring to run leaner, you're really just keeping the flapper from opening as much as soon, "tricking" the ECU into thinking there's not as much air coming in. So.... it thinks there's less load, and you end up running more timing.

Stock NA ECU + More timing = bad.
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Old 08-18-2012, 11:28 AM   #29
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you said that #4 cylinder wasn't effected when you disconnected the spark plug wire yet you switched plug wires around still #4 didn't do anything?

Did you try disconnecting fuel injector connectors while its running? You may have a bad fuel injector on #4. Disconnect it and see if it changes engine note or not. If it doesn't change engine note, swap the #4 injector to another cylinder and see if its dead on that cylinder.
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Old 08-18-2012, 05:17 PM   #30
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Maybe the injector cables?? Because i was using my 1.6 injectors and it did that so i went with 1.8 injectors and it still did that

Im gonna do the compression teat but i want to make sure i have all the steps right
Warm engine up to normal temperature
Unplug all spark plugs
Unplug cas
Plug in the tester to the cylinder
"Depress" gas pedal??? How do i do that???
Crank it a few times how many?
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Old 08-19-2012, 03:50 AM   #31
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Make sure you unplug the coils, pull the fuel injector fuse, .. floor the gas during cranking.

I'd recommend having a charger hooked up to the battery while doing this test. Crank for 5 seconds. (Not 5 whirls of the charger)
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Old 08-19-2012, 08:26 PM   #32
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And pull all the plugs. You tape the gauge to the windshield if you dont have 2 people. Gas pedal all the way down, and turn they key like you're starting it. I'll make a blubing noise, you want 6 blubs.
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Old 08-20-2012, 12:47 AM   #33
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The gauge comes out 2-3" above the cylinder head.. you dont have any room to tape it to the windshield.
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Old 08-20-2012, 01:02 AM   #34
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Quote:
Originally Posted by triple88a View Post
The gauge comes out 2-3" above the cylinder head.. you dont have any room to tape it to the windshield.
Depends on the gauge. I've used a few where there is probably not even 2"-3", and another where there would probably be room to tape it to the windshield on cylinders 3-4.
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Old 08-20-2012, 10:47 AM   #35
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So let me clarify something here...

Your car was running with one turbo setup. It had proper vac. at idle and was smooth running. You then replaced a bunch of parts and did not driver the car, just started it back up and at this point the idle went out of whack? Or did you install the new parts, have a smooth running car, drove it and now its acting up?
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Old 08-20-2012, 10:53 AM   #36
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Had one turbo setup was running fine upgraded parts started it and it was out of whack i didnt get a chance to drive it. Replaced manifold (old one was already welded once so decided to upgrade) downpipe and turbo (turbo needed rebuild so i just installed another one) and added intercooler thats it. I started it and it was all bad so i thought maybe the injectors so i wemt with 1.8s but that didnt change anything
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Old 08-20-2012, 11:13 AM   #37
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Your video sounds like you have a major exhaust leak before the turbo. Were there pipe plugs in the number four exhaust runner to block the EGR port and the port on the underside?
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Old 08-20-2012, 11:16 AM   #38
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OK, that is helpful to know you didn't drive the car and pop something.

Have you put a timing gun on it? Had you messed with the CAS setting?
Generally, a vac. leak will cause a lower idle and reduced readings on the gauge, but not the surging. I wonder if it's a timing issue.
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Old 08-20-2012, 11:17 AM   #39
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Yeah i thought thats what it sounded like too so i redid my exhaust manifold gasket but no plugs anywhere on the new parts
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Old 08-20-2012, 11:19 AM   #40
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Yea my timing is at 10 i didnt mess with the cas again i have msd on it but it was on there since my last turbo setup
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