When i hit high RPMS in 3rd 4th or 5th all power cuts off to the engine…Its not RPM limiters or the governor(gear sensors are unplugged and im not hitting 180). Im almost possitive its the MAFS because ive cleaned mine with engine degreaser and used the air line to blow all the crap off of it. After doing this the problem goes away but then a month or two down the road comes back haunts me…in 5th i cant go higher than 3500rpm…i kno i should’nt be but what if i need to pass sum1 :roll:… I bought a used one same thing…ill try cleaning this one if the problem goes away its deffinatly got to be the mafs. Im swapping this new one i bought with another one off the same guy i bought it from. If this works awesome…if not wtf is wrong with these sensors or the computer. Any ideas on troubleshooting this incase its not the MAFS…im pretty sure i have my finger on it being the MAFS…try unplugging your mafs and driving around…ull feel that exact same loss of power as i do. maybe time to upgrade the mafs anyways??? maybe that will solve my problems and need for power in the future. Anyways teh cars a sohc and has a injen intake if that makes any diffrence and i got one of those silly breathers…but the hole on the intake is covered…i gota get rid of it i kno i kno…their pointless and i dont want a 100+ ticket.
-Devin
could also be your ignition breaking up under heavy load, change your sparks wires cap and rotor, you should prob do it anyways just general maintenance stuff.
Yeah - In high load pulls my shit breaks up when the motor gets hot. I’m pretty sure it is crappy old coilpack related. I’ll be upgrading.
However, this happens at about 5000rpm…
I suspect you may be MAF related if you are hitting the wall at 3500rpm though!?!
yea its really weird, dude id have to suggest trying the new mafs first. i hate crazy intermittent problems my MR2 had an infinite number of them i know how you feel believe me
gay…3rd MAFS i swapped in cleaned it many times with engine degreaser swapped the WHOLE mafs Just incase…didnt just swap the sensor itself held in with 2 screws…I suppose im looking at the wires, plugs etc etc. now…everythings fine up until 3rd all threw out the rpm range. Ive checked the ECU before nothing popped up…If i can remember i left the ECU lights visable and took it on the highway hit the brick wall and the red light started flashing…but no error codes showed up…weird. now how do i go about checking the distributer…? what would be worse is to not have the car run because i broke sumthing because ive never played around with a distributer cap on one of these cars. Ill check it out on my 91 1st…Are the distributers swappable? ka24e and ka24de…Thanks…this sucks hopefully ill get it figured out.
-Devin
It could be fuel related …
That’s the most frustrating part with intermittent problems. You play with one part for a week, think you’re making progress only to find out it had nothing to do with it at all.
The only other thing I can suggest with the MAF is to look at the actual MAF wiring. Is it frayed? Are the contacts all crapped up?
Does the plug still have the retaining clip to hold it in place? A loose MAF connection can cause all kinds of stupid running issues.
I thought fuel at first too…went ahead and did the lines and filter but no luck…possible the pumps breaking up at high rpms :dunno:. can anyone describe the feeling of the feulpump giving out on them at high rpms? Ohh and when my engine cutts its still running…doesnt bumpstart itself ive tryed clutching in as soon as it happens…but if i continue to give it gas nothing happens…even letting off and giving it throttle…it will drop about 1000rpms slowly before i can get power back…doesnt sound like fuel issues…we’ll see what a baster SS coil does and rotor/cap.
-Devin
When the fuel pump in my 200 went, it took a few weeks.
At first I didn’t really notice it, because it would only happen at high RPMS, in 3rd gear under serious load. I thought it was just my plugs being snuffed out. It kind of just hesitated at about 5,800 rpm. It wouldn’t go over it, but it didn’t stumble or backfire or anything.
Then it started happening at the top of second gear, and 3rd it would just chug. It was like hitting a wall. The RPMs would drop to idle. If I tried to give it gas, it would just die. It wouldn’t stall, it would just not go. If I downshifted to second, same problem. Come to a complete stop, and it would work fine. I could hammer on it again in 1st, right up to halfway through second then spud right at the same RPM, it would cut out again. I was 100% sure it was ignition, because it always seemed to happen at the same RPM.
Eventually, it got so bad the car would only idle. As soon as you tried to move, it wouldn’t.
I changed everything electrical, even custom made my own ingition setup, nothing. Pulled off the fuel line, stuck it in a bottle, turned on the pump and … it slowly piddled into the bottle.
Out came the pump, in went the 320 Carter and problem was solved.
^^^^^^^^^^Hmm…possibly…i was just coming back from work thought it be funn to burn out at a set of lights with buddy behind me…it did it in 2nd 
…its working its way into the lower gears so it could actually be the pump. Thanks for the advice…i geusse im looking for a pump…Ill still do wires cap/rotor and the coil but one at a time so i can nail what was wrong. I remember when i got the car i fixed a leak and those nuts that fasten on the wires to the sending unit were pretty bad…Whats the wireing like for the pump…4 wires…? anyone got the colour codes and what the wire does? i might as well fix up the wiring while im at it. I think before this im going to get someone who knows enuff to come with me for a spin get their input. Any one up for that? ill just start askin a few guys. take it ez
-Devin
Alllriight…So i changed the pump to the 255…fuel sending unit nipples were boinked…big mess spent sum more money on that its running smoother starts up real snappy…but im still hitting the wall…its at about 4500rpm in 4th i hit it on the way to work…I think what im going to do is catch it on video show everyone exactly what its doing and hit the wall a few times trying diff things like working the gas pedal, clutching in then reving, just a quick clutch in etc etc. So im back to thinking its electrical. If its wires it would be noticable threw out the entire rpm band correct? Possibly rotor/cap or im more leaning towards the coil. So im upgrading to the SS blaster…as i think the cap/rotor breaking up would be a little more random. Any other tips/advice? This is getting really annoying. Sum done up corolla was flashing his highs at me trying to get my to pull into a tims on the way home…if only…*sigh
Whens the last time you changed the fuel filter? Could be clogged.
One of the 1st things ive changed. :?
You guys don’t even want to hear hte story of the fuel pump failing on my MR2. I had to have it towed 4 times, stranded in random places. It was the worst because it would always “fix itself” overnight, so even when it was left at a shop to be fixed no one could figure out what was wrong.
What a nightmare.
^^^
That was like Danner’s silver 200sx. Closing the hatch would make it come back on.
I know in my heart of hearts that it should have been wiring related, but it wasn’t. (possibly internal in the pump?)
You’d drive around, car would start to sputter, then come back, drive fine, start to sputter, die. You get out, pop the hatch, jiggle everything, whack the tank, etc. Get frustrated, slam the hatch then whirrrrrrr you’d hear it come on.
So we changed the wiring, gave it 14V hot, nothing. Still had to slam the hatch to get it to come on. Swapped the pump and no more worries.
Just an update on wtf is going on. I took the highway…usually never have to but i got up to 4000 rpm in 5th…few minutes later i could only hit 3500 then few minutes again i can hit 4000. getting off the highway i rip it in third hit the wall at 5000. Now on the highway i tried just for the heck of it continuing to hold the throttle down as rpms are slowly droping while i have no power then whack it snaps back in after it drops 500rpms or so…Hmmm…Its hitting these walls pretty accuratly. can anyone really sudjest anything else…I havnt touched the cap/rotor or coil. Thats the next job im going to tackle.
When you get these gremlins, what happens when you sit in neutral and rev it to 5.5k or so (no load on engine)? Does it max out at 5k all the time when you are sitting and revving it in neutral?
I found a similar problem thread for SR
the cars absolutly fine with no load. I can punch in the clutch when i hit the wall and redline if i wanted. Only breaking up under load.
If it really is the maf:
Go borrow someone’s SAFC… wire it up (it’s only 8 wires or so)…
do a reading on your MAF.
idling should be pretty stable at 2% flow
redline should be no more than 70% flow (on a KA).
If these are similar to the numbers u’re getting, it’s not the MAF.
Bet you any money i’ve had my car towed more times than you do. Btw, i remember talking to you before and i think you bought your MR2 from the same place I bought my 240. 
Hmm, devin, i don’t know if this helps but when i was wiring up my safc, it was wrong at first and that caused my rpms to not be able to go above 3000rpms, it would just bounce off as if it was a rev limiter. Did you touch your wiring by any chance? I would check the maf wiring and maybe the wiring going to the ECU. Unless you haven’t touched your ECU at all. Could also be the ignition coil.
you keep saying you cleaned your mafs with degreaser that could @#%$ all 3 of them up that you changed. you arent supposed to clean mafs with anything enless you wipe it with a clean rag or blow it out and some mafs clean themselfs its called a hot wire when you shut off the engine the wire gets really hot to clean the dust and dirt off. when you wet it you most likely ruined the little computer in it. it might still be the maf but you keep messing it up with the cleaner.