sound

[valenzul]

ok. I notice that my BPT engine makes this kind of taping noise like 2 simultaneous screwdrivers taping on the intake manifold. then I look at timing and it pulls way back to teh left when this noise occurs.... this is when it is warmed up and it is only around 1k RPM. Is this pinging/detonation?

[Franko]

If you are referring to the tap tap tap noise that is enough to drive you crazy coming from the engine then it is not pinging. This noise is the hydraulic lifters in the engine making a tapping noise. It usually goes away after you drive a little bit when the oil pressure builds up enough. I noticed the sound occuring more when I changed to synthetic oil because all the "gunk" got cleaned out that was muffling the noise.

I cant explain the timing changing.. When you say that it is pulling way back to the left do you mean that it is advancing or retarding?
And what ecu are you using with your bpt?

OHH it just hit me.. My car is using the stock mx-3 ecu.. I have an apexi safc2 running with it to fix the fuel curve.. When ever that noise occurs I can see knock on the safc.. The safc thinks it is knock but it actually isnt.. It just looks like it is.. I am willing to bet that you have a ecu that is reading the knock signal. Like a reprogrammed protege ecu or a real bpt ecu. In either case these both have a knock signal input on them for the knock sensor.. When you ecu is reading what it thinks is knocking it is most likely retarding the timing of the engine to try and get rid of it.. My mx-3 ecu has no input for knock so my timing is the same all the time.. I am going to get a msd ignition that will automatically retard the timing per pound of boost.

As for the noise the only way to get rid of it is to change out the lifters which requires a rebuild. Otherwise dont worry about it it is doing no damage. It just makes it sound like a diesel or something

<small>[ August 17, 2004, 08:09 AM: Message edited by: Franko ]</small>

[valenzul]

yeah... I figured it was not knock cause it is way too low of RPM. But damn HLA that loud!!!!
I had HLA on prior 1.6 and it is was not that loud. This one scared the **** out of me and I would bring the throttle down just to make it go away. I'm running BPT ECU.
thanks for your response. is your check engine light working?

[papa roached]

try running some synthetic oil through it, they might be really dirty

[perhapsadingo8yerbaby]

Originally posted by valenzul:
ok. I notice that my BPT engine makes this kind of taping noise like 2 simultaneous screwdrivers taping on the intake manifold. then I look at timing and it pulls way back to teh left when this noise occurs.... this is when it is warmed up and it is only around 1k RPM. Is this pinging/detonation?

Could it be a timing belt tensioner making all that racket? I recently suddenly aquired a noisy tapping sound on my 2.2L '90 MX-6. Was convinced it was lifters but now have further isolated it to actually be coming from the timing belt cover so most likely mine is an idler pulley or t-belt tensioner. Have you put a stethoscope on it? Just a thought...