STILL NO IDEA

[craz4240]

Car is 1995 240sxRB20DET300zx MAFSeries 5 RX-7 InjectorsGTR FMICCustom built rb25 turbomanual boost controllerFPRInnovate WidebandCarl H tune

Heres the issue the car is running super lean under idle 22.4:1 and super rich under ful load 7.8:1,it spits like real hard like an exhaust leak or air leaking out.I am fairly certain I have no boost leaks,I am a little unsure about my turbo gasket but will address that but can't see that causing this issue.

It is mushrooming the plugs from egt's being real high.I have changed pretty much all hoses on the motor and blocked off the couple unused vacum lines.I have changed the lower injector isolators for thicker ones...all to no avail.

This is a good one for those who like a challenge all I need is this issue fixed then I can go onto driving this damn car lol.

NRRBA reins!!!!!!!!!!!

[Kansei240sx]

You dont have any air leaks after your MAF do you?Vented blow off valve?

Make a pressure tester out of a silicon coupler and a PVC end cap, and put a air chuck attachment to it. Pressurize the turbo inlet or outlet and removed the PVC hose and block it off while doing so.

Get a bottle of soapy water and spray it around your couplers and all links where air could escape, check around the intake manifold, throttle body and all other flanged surfaces in the system.

Check you Cylinder head temerature sensor, and also see if you can find out what your fuel pressure is at through all ranges.

It almost sounds like a hardcore vacuum leak. I could be wrong, but in experience, there may be a slight or major vacuum leak after the MAF and the engine doesnt see that air coming in so at idle it is lean, that or your timing is off hardcore. So when you get on it, the ECU sees that you're running lean and dumps fuel hardcore to compensate. I could be wrong though considering i dont know how carl does his tuning.
Modified by Kansei240sx at 6:04 PM 4/9/2008

[craz4240]

I think your 100% correct here...i have tested for boost leaks the exact way you have said.Nothing came up......I am as per carls advice leaning towards a bad intake gasket....but any other advice would halp immensly guys.

[craz4240]

Anyone else??? I am definatley replacing the intake gaskets etc. here soon.

Any input is awesome...

[S14-NEO]

you can checl the intake manifold gasket for leaks by using a flammable brakeleen and spray the flange of the manifold that mates to the head...if there is a breach the vaccum of the engine will suck it in under an idle condition...you will notice it immediately cause te engine will raise in RPM and level out, that is if the engine idleing poorly

[craz4240]

Yes I will have to try this again...getting time on the hoist at work has proven hard seeing as how I am on the OHS committee,I work late 2 or 3 days a week,have a fiancee,mother with a broken hip and a grandmother I look after.

I am wondering if pressure testing just the intake mani..via throttle body with the pcv system blocked off might tel me something as well.

[craz4240]

Can anyone comment on how noisy series 5 RX-7 injectors are?

[jdmser]

For as long as you have been looking for boost leaks I think you would have found it by now. Have you had the injectors flowed? I know when I was running super rich that the wideband was showing lean because the fuel wasn't able to atomize so that the sensor could read it. Also, have you tried swapping the maf out for a known good one?

[craz4240]

Yeah man it's not a boost leak it's an air leak of some sort,i know I am getting good fueling and spray patterns,I am leaning towards intake gasket now.Just wondering if anyone has had any expierience with series 5 injectors.....these ones are hella noisy.