I must say the install was fairly easy.

toughest part was removing the strut bar bolts ( I almost busted a vessel!) and getting those damn 6 internal gasket spacers to stick.

After install - I test it listed for air leaks - sure enough a high pitch sound go off as soon as I turn on the engine. shut off engine- check for loose bolts - yes, a few. test again no more sound.

test drive - HKS muffler is way louder than before. car is idling nornally at 1500, 1000, 750 rpms. So I go for a run and at the first stop light - PROBLEM - car starts to choke up a bit below 750 rpms.. in fact, it drops to 500 rpms and tries get back up to 750 rpms.... I thought the car was going to shut off.. It does this at every stop light. Seems like it does this if I am idling for more than 30 seconds.

HELP - I don't like this. what can be done to eliminate this "choking" effect?

BTW - I do have the JWT popcharger installed as well. I think my miles per gallon is going down - cause seems like it rides with higher rpms than before.

Other than that issue - car feels like it has more power.

Thanks for feedback!

 

your idle should NOT be lumpy, chokey and inconsistent -- if it is, its a sign that theres a vacuum leak most probably due to the spacer.

 

Sounds like possibly a loose connection from the intake tube to the throttle body. You might want to recheck to make sure the clamps are tight.

 

when cold...go back and recheck all tubes. re-tighten intake and if needed....unbolt losen all plenum bolts and be sure to tighten them down in the order listed

 

Thanks for the advice - dang it - did not realize there was an re-tightening order
Will check all tubes.

 

warning: please take extreme caution when tightening things... use a torque wrench...

 

also check to see if the rubber cuff around the oil cap didnt accidentally get sandwiched between the upper and lower collector (plenum) or spacer.

 

INSTALL IS COMPLETE AND CAR AT IDLE = FINE

2 things I discovered this morning:

1. some bolts were loose enough to untighten with hand.

2. Part of the RUBBER BUFF around the oil cap got caught between the 1/4" space.

* also followed the order sequence to tighten
* don't know how to reset ECU - so I just discinnected the battery completely while working on the spacer again.

Thanks again for the replies! From them it sounded like it would be as simple as what I found. Thus, allowing me to put it aside till this morning.

 

whats up i had a low idle with my plenum spacer too so i just went out to check the oil cap thing and sure enough, there it was right inbetween the lower manifold and the spacer... so i take it off and get the rubber out of there and start tightning up the bolts when low and behold i snap one of the outer bolts right in half...i'm like **** and luckily i have an extra one. It took forever to get that little ***** off and then procede to to tighten them all up again....so on the last one i ****in snap another one in half....so now i need to get another bolt from the hardware store...my idle slightly improved from before but i still need to get another bolt for the rear of the plenum... i couldn't believe that i broke 2 freakin bolts...hopefully tomm i'll have it all fixed... oh yea i installed the spacer at night so thats my excuse for the oil cap rubber getting in there haha... idle right now is about 650 after warm but drops very low when shifting into neutral before raising back up to 650...whats it supposed to idle at again when normal and at operating temp

 

how much would this effect performance besides the idle?

 

350ZWarz,
The rough idle sounds like the symptom of a leak. When you installed the bolts did you use a torque wrench? Too much torque or uneven torque can cause a leak.

It should go away when you put in the remaining bolts. Let me know how it goes.

Tony

 

yea i'm pretty sure it is leaking because the bolt in the back broke off and i haven't got a new one yet, i didn't have a torque wrench either which is why i broke them. i wasn't even holding the wrench by the end just right over the socket, i guess i don't know my own strength

 

got a new bolt and it looks like it is idling at about 750 now and does not drop low when shifting into neutral...hopefully it's all good now