www.86garage.com

I was referred here by NST, and the problem I'm having is this:

It's for a 1986 MR2 AW11.

I have my timing set at 12*, and when I rev the engine, it jumps up to 55*. Scary stuff.

Recent activity in the engine bay include:

complete teardown and rebuild
bored .040" over
all new Toyota hoses and gaskets
new tune up components from Toyota (cap, rotor, wires)
RS*R header
egr delete
NST triflow cams
Adjustable cam gears set to cam card specs at the machine shop

The engine fires right up and idles fantastic.

Any suggestions?

did you follow the correct procedures for setting your timing as per the FSM i.e. jumpering the service plug and setting distributor to recommended timing, etc...

Yes I did. I keep the special "tool" (paper clip) with my ratchet set.

ok question for you ...

so it hits 55 deg like when you rev it does it return to 12 deg when it idles instanly or takes a while... how does it drive ... any hesitation or does it climp those rpms quike and then have no balls at top end (highway speed accerleration.) ?? really need to know or make a video of the engine running and reving.. also if you ever need a 5 speed trany for your mr let me now i got one laying around lol..haha..

mbehrens wrote:ok question for you ...

so it hits 55 deg like when you rev it does it return to 12 deg when it idles instanly or takes a while... how does it drive ... any hesitation or does it climp those rpms quike and then have no balls at top end (highway speed accerleration.) ?? really need to know or make a video of the engine running and reving.. also if you ever need a 5 speed trany for your mr let me now i got one laying around lol..haha..

It returns to 12* as the rpms come down. It dives alright... but I had more power out of it when I had a blown piston. Considering the timing issure, I haven't taken the rpms over 3000, and wouldn't dare take the thing on the highway.

Thanks for the trans offer, but I'm looking for a c160 six speed.

how is the snap throttle does it hesitat or accelarte real quike like a rabbit repreducing lol..

you know what give me call and lets see if we can figure this thing out.. number is 210 326 6648

I'm so sorry! My phone died! I'll go ahead and tear into it and clean it real well as we discussed.

on your distributor check your pick up coil wires for ohms between 130-190
also sense you rebuit your motor ..
here are the quistions.

did you remove the tps?
did you check your maf sensor... when my 86 mr2 i had a few years ago started to heitate when throttling and snaping. but idled fine the maf sensor was dead...
let me now...

tps was never removed from the throttle body, and the MAF isn't throwing a code. The car can fire right up, and you can rev it up, it's just under a load the timing goes crazy.

Hmm... I measured 185 most of the way around, (I rotated the shaft 360* as I was measuring), and it spiked up to 190 at one point. I got the same measurement out of both connectors, since I wasn't sure which one to measure for certain. Is it acceptable to have these measurements out of both of them?

Cleaning it out and putting it back in didn't do anything for me. I'm tempted to buy a new distributor just to make sure I can rule it out.

Also, I just checked resistances again after it had a chance to sit awhile and get room temperature. It now measures about 160 ohms.

that sounds about right.. the ohms ...

but yeah umm so you cleaned the pickup coil sensors and it still doing the same thing. . .

if the pickups good and the ignitors good and the ecm is good i bet its the maf. also did you add any sort of intake? sometimes it turbulates the air before the maf and scuwers the readings.

the ecm is telling the ingitor to fire at that degree so i would suspect a sensor input problem. if engine timing and cam\crank position sensors are within spec. then i would first go to the maf then to the ignitor and then suspect the ecm if all else is good.


do you have another dizzy? do you have another ecm or maf or ignitor\coil you can verify that the ones you have are good?

well panic and i talked and it seems to looking like his tps went out on him the ohms are not there incorrect if you may say lol... o he going to double check but thats what looks to be the problem..