i started using preimx in my 88 TII and noticed my vacuum at idle is going from a steady 16 to 15, somtimes 14. sometimes it bounces from 16 all the way to 12. all this is at idle. when im cruising or racing she runs perfect. in the mornings when i start her up i'll see 18 on the vacuum gauge at 1100 rpms. i put 8 ounces to every fill up and still run the omp. is this cause the premix or possibly a vacuum leak???

i was wondering if any of you guys are experiencing the same thing??

thanks,
jae

 

i think im gonna skip putting some premix on my next fill up, then after go to 4 ounces every fill up!

maybe that will work.

 

It's gotta be a vacuum leak as 2-Cycle oil is only going to increase your compression, thusly giving you a higher vacuum.

Or it could be bad seals...but I'd bet my *** on a loose vac. line or gasket.

 

Uh, my TII has been running 14 psi vacuum at idle since I replaced all the vacuum hoses with silicon. It gets moody sometimes, and cycles between 12 and 15. Been doing this over a year now. No premix, stock OMP (87, mechanical). Runs and idles beautifully. Compression, however, is in the low 90's. You mean to tell me this isn't normal!??? Dayamm, I better forget about the Hi-6 ignition and fuel cut defenser, and work on this vacuum "leak" nonstop!

Irv, Keith's dad

 

Irv, your engine is toast and the car is too dangerous to drive. Remove all serviceable items and send them to me for disposal. Please pre-pay all postage. There will be a handling fee, so please inclose a blank check with your signature and also all your credit card numbers. Buy a Yugo as a replacement vehicle.

 

a healthy engine should read 18/16 on the vacuum side of your boost gauge. this is what i read from different rx7 sites. 16 is good 14 is not so good. 10 or under and you got a serious leak or your motor said goodbye to you!!!


im starting to think it has somethin to do with my bac valve. anyway im taking my t-rex to the local rotary mechanic 2morrow to get my brakes done so i will bring it up to him, maybe he can fix it.

maybe my primary fuel injectors are taking a **** on me!!

 

Wait... In rotaries with premixing and crap. Do you use 4 stroke in the main oil fill, with filter and stuff, and 2 stroke in the mix?? Can someone please specify. You use regular motor oil right?? Explain the mixes and what combos i use. I was an outboard mechanic for quite a while so I know quite a bit about 2 STROKE engines, I noticed teh 2 stroke portion and wondering how 4 stroke comes into play.

 

i use mobile 1 full synthetic motor oil in the engine and valvline certified 2 stroke premix in the gas tank. i buy mine at discount auto parts.

8 ounces to a fill up and i keep the omp working