Seriouse problem with air intake and pre detonation

[mikeetown]

I'm going to get s youtube vid of this tomorrow. I've taken apart stuff 3 times now. Intake and all sensors and so on. My intake is leaking an excesive amount of air from inside the throttle body. Huge hissing sound.

My k8-ZE is pre detonating at random times. Sometimes a lot and sometimes a little. I'm so stuck and i'm so pissed cause i need a car running ASAP.

Please help guys. The vid i will post wil dumbfound you.

When i start the car it revs to 4000rpm right away, wont stay running unles the VAF is unplugged..... lol what the heck is going on!!

[mazdags94]

"serious problems with triple posting"

I would start by fixing the vac leak (new intake) and potentially the VAF. Start by replacing the intake and see what happens. The car shouldnt stay running if the VAF is unplugged; the ecu needs info on how much air is going into the engine to control fuel, in conjunction with the TPS, CTS, and O2 sensors (a/f ratio). If the mixture is too lean, you could have a higher temp in in the combustion chamber and predetonate.

Are you throwing a CEL?

[Inodoro Pereyra]

I agree with Mazdags94.

Take care of the leak. That's the most important part. Make sure you don't have a vacuum leak elsewhere.
If that doesn't solve the problem, you should have a sensor problem, which means you should have a CEL. If you do, get your codes. Anyways, before you start replacing sensors, get a can of contact cleaner. Most of the times it's the connectors that are dirty, not the sensors.

And take a close look at your knock sensor. If it's working properly, your engine should NOT detonate, ever.

[projectzemx3]

"serious problems with triple posting"

I would start by fixing the vac leak (new intake) and potentially the VAF. Start by replacing the intake and see what happens. The car shouldnt stay running if the VAF is unplugged; the ecu needs info on how much air is going into the engine to control fuel, in conjunction with the TPS, CTS, and O2 sensors (a/f ratio). If the mixture is too lean, you could have a higher temp in in the combustion chamber and predetonate.

Are you throwing a CEL?

not true, if the car is running and you unplug the vaf yes it will die out, but if you start it with the vaf already unplugged it will run.

i am thinking it is probably something simple. possibly just timing.

[94mx3precidia]

Spray some brake / carb cleaner on the intake or suggested spots that you think are causing the vacuum leak. If the engine revs up slightly you found the leak.

[mazdags94]

"serious problems with triple posting"

I would start by fixing the vac leak (new intake) and potentially the VAF. Start by replacing the intake and see what happens. The car shouldnt stay running if the VAF is unplugged; the ecu needs info on how much air is going into the engine to control fuel, in conjunction with the TPS, CTS, and O2 sensors (a/f ratio). If the mixture is too lean, you could have a higher temp in in the combustion chamber and predetonate.

Are you throwing a CEL?

not true, if the car is running and you unplug the vaf yes it will die out, but if you start it with the vaf already unplugged it will run.

i am thinking it is probably something simple. possibly just timing.

Maybe it's just me but my engine wouldn't start/run unless the VAF was plugged in .

[mikeetown]

thx u guys.

so far, i've replaced the disti cause i had to.
-I checked the hard timing and its bang on (belt and cams)
-I just threw codes 2 and 5 all of a sudden which is knock and crank. If the crank position sensor didnt work though the engine wouldnt run right?? And i guess i should use the knock from my K8-DE and put it in my K8-ZE. It was working for sure.

Why should i replace the intake if it was previously working in great running condition??? I just took it off my running engine. de to Ze intakes are different but bolt on cause they work the same. The design is different for jap market with no EGR valve.

It runs like a bag still

[mikeetown]

thx u guys.

so far, i've replaced the disti cause i had to.
-I checked the hard timing and its bang on (belt and cams)
-I just threw codes 2 and 5 all of a sudden which is knock and crank. If the crank position sensor didnt work though the engine wouldnt run right?? And i guess i should use the knock from my K8-DE and put it in my K8-ZE. It was working for sure.

Why should i replace the intake if it was previously working in great running condition??? I just took it off my running engine. de to Ze intakes are different but bolt on cause they work the same. The design is different for jap market with no EGR valve.

It runs like a bag still

[Inodoro Pereyra]

Remember that CELs don't tell you that a sensor is bad: they tell you the READOUT from that sensor is inconsistent, or off spec. You may have a perfectly running sensor, but if you have a problem down its circuit (like a dirty connector, or a frayed/cut wire), or a mechanical problem that affects it (like a broken tooth on the harmonic balancer's crown), you will get a code anyways. You need to check those sensors, their circuits, and their actuators, and see what the problem is.

[mazdags94]

thx u guys.

so far, i've replaced the disti cause i had to.
-I checked the hard timing and its bang on (belt and cams)
-I just threw codes 2 and 5 all of a sudden which is knock and crank. If the crank position sensor didnt work though the engine wouldnt run right?? And i guess i should use the knock from my K8-DE and put it in my K8-ZE. It was working for sure.

Why should i replace the intake if it was previously working in great running condition??? I just took it off my running engine. de to Ze intakes are different but bolt on cause they work the same. The design is different for jap market with no EGR valve.

It runs like a bag still

Are you referring to the intake manifold?? What 94mx3precidia was suggesting was to check the accordian intake tube that goes into the intake manifold. Being so old, you may have caused it to tear just by removing it and reinstalling it. You could always upgrade it to a solid, aluminum pipe intake.

[solo_ryder]

Seriouseeeee

[Inodoro Pereyra]

Seriouseeeee

[solo_ryder]

Seriouseeeee

Sorry I couldnt resist, I see this thread every day for the last week or something and I laugh everytime I see the title.

[Inodoro Pereyra]

I know.

Every time I see a thread like this one, I start lurking, waiting for somebody to say something...

[mazdags94]

It's hard for me to take this thread seriousely now....