86Rx7GXL

WEll the car at least idles now, i got the intake all sealed up. But now and still theres a hugh stumble, hesitation missing not sure what to call it above 4 grand. wether im driveing it or just reving it up in neutral. i have the timing set right now too. also i dont know if its boosting to much. In 5th gear about 3 grand floored how much boost should there be on the factory gauge? also i dont think im hitting a fuel cut cause it does it just reving it to. does any one and any clue what to look at what may cause something like this? also the TPS is good and set right.

menace

clean ur secondary injectors.

86Rx7GXL

There brand new, i suppose there working alright i've switch them with the primarys and the car still runs the same.

86Rx7GXL

anybody know of anything? and about the boost i know the factory gauge isent right 100% but how close to that +40 should it be? when should it reach full boost?

86Rx7GXL

anybody?

Keith

Sounds like you are missing the infamous pill that goes in the line to remove boost spikes. Remove the vacuum line that goes to the pressure sensor and try blowing through it. If it is easy, you need the restrictor pill, go get one from Mazda or a boneyard (a new one is less than $5).

MasteRX

If you are getting one from Mazda, you might tell the part guy to search for "orifice", that is the Mazda description for it. The local Mazda parts guy here couldn't find it in the computer until I told him to look for that.

86Rx7GXL

alright i went and blew threw the line that goes to the pressure senser. it was easy but shouldent it be? cause all it does is go into intake manifold. Well into the ACV then into the intake man. Am i wrong? what does that pill look like?

86Rx7GXL

Anyone? whats happening without that pill in that line? what is its purpose?

Keith

The purpose of the pill is to smooth out the boost signal to the sensor. The actual boost signal has a lot of spikes and surges that cause false readings. With the pill in place, a spike will not make it to the sensor. If it did, you would get a false fuel cut signal. So no, if you can blow through the line easily, it is NOT normal, you have a problem. Like I said above, go get a pill.....

Irv, Keith's dad

PS here are the conversion figures for the stock guage...
The boost guage reads out in units of millimeters of mercury. We like to see our pressure readout in psi (pounds/square inch). The conversion factor is .1934. Crunching thru the figures, we get:
5 = 1.0 psi
10 = 1.9 psi
15 = 2.9 psi
20 = 3.9 psi
25 = 4.8 psi
30 = 5.8 psi
35 = 6.8 psi
40 = 7.7 psi
On my boost guage (when the fool thing decides not to stick at -20!), I get a reading (max) of 35 in first and second, with it creeping up to 40 in third. I put a boost test guage on the car, and it read 7.0 psi in first and second, and a little over 7.5 in third. So, you see, it corresponds very well.

86Rx7GXL

Hey thanks, do you think with out that pill it could cause a high rpm stumble? Maybe it could be cutting fuel on a spike just for a spilt sec over and over. i dont know would that be possable

HAILERS

UhHuh.