schwass

Hey there people, my name is mark and im just after some help with my, 1999 rx7, the problem is that it has started stalling, (makes me look like a fool) and this problem is becoming a pain in the ***, it make the car pretty mych undrivable for my partner, the story goes,

I will be driving along, come to an intersection, traffice lights, driveway I put my foot on the clutch or take out of gear and just sit in netural with no foot on clutch and the car will just randomly stall, 90% of the time. i have searched and found that it could be many things, dashpot ( whice i have adjusted), tps but i dont think it is that as the car runs fine and when ideling it is constant not up and down or rough, if i sit there with the revs up above 1200rpm then no stall, i have a power fc and commander and have adjusted my idel up as high is it will go, 1000 to 1100 by memory, and it still stalls,the other thing i have read about is the clutch switch, but it stil stalls when the clutch is not used, ?? I have replaced plugs, leads, fuel filter, but it is still the same, any help would be appreciated. thanks mark


A Quick run down of mods and history,
K&N air filter element in original air box, power fc and commander, the cat has been removed, after market blow off valve, and i think that that is it, the car has done approx 155,000 km of the original motor, and was compression tested after this problem arose, and i was told that it was fine, hope this is enough any questions just ask thanks again mark

weetbix13

155,000 kms on the original engine? haha, no way!
what is the vaccuum reading at idle?

schwass

hey sorry, its 152???km on original engine, at an idle of 900 rpm ( when i can get it to idle lol) the vacume reading according to the commander is 400 mmhh am sure on the 400 but not the mmhh, hows that sound??

weetbix13

idle is high at 900 - normal is around 700 but thats nothing to worry about.
400mmhh? thats gotta be mm's by something... i'm gonna stab in the dark and say it is equivalent to around -0.4BAR since it is japanese measurement.

mine idles at -0.5BAR so that doesn't seem out of whack too much.
where in NZ are you based? there are a few people on this forum who know a bit about these in NZ who may be able to come and look at it with you.

KeloidJonesJr.

iTrader: (8)

TPS? You are now plagued by the problems with 2nd gens.

weetbix13

i can't see it being TPS - he considered it but hasn't reported transition issues or anything... nor any bucking.

oh, not to be a naysayer... but that is NOT the original engine at 150+ kms!
feel free to flame everyone, but i would be AMAZED!

schwass

yeah the idle is high cos i adjusted it with the commander in attempts to stop it from stalling, it was set at about 800 originally, im just out of te puke, bout 45mins from tauranga, where are you based?

schwass

I got the car at 112???km and have now clocked it up to 152 i havnt re-built it and i am first nz owner, the car dealer said it hadnt been rebuilt.

weetbix13

not saying i don't beleive car dealers but even at 112km is starts getting iffy.
i bought mine at 116km and I KNEW from my research that the engine was a goner within a year - sure enough, one week after i bought it it threw an apex seal and (after a long legal process) I rebuilt it myself.

I would hazard a guess that it was rebuilt before you got it - if not then it'd be good if you could post your compression test results cause it could be well and truly into the danger range for apex seals.

I'm based in Auckland so probably can't do the old day trip to help you look at it but feel free to mission to Auckland

couple of questions:
1. is it easy to start?
2. any smoking?
3. does the car shake at all on idle?
4. when the car is idling, is there any smell (rich/oil/other) and does the airpump run?
5. what is your boost pattern?
6. is transition happening at 4,500 like it should?
7. does it feel as fast as normal?

1QWIK7

iTrader: (33)

Check your clutch switch.

Go by your clutch pedal (you have to actually look under your dash) and press the clutch with your hand, there will be a switch by the clutch arm before you press it. When you press the clutch, there should be a white skinny button thats supposed to come out as you press the clutch.

Maybe the spring inside got stuck or getting stuck.

weetbix13

and if it is toast - search for the ballpoint pen spring fix!

schwass

Thanks guys, I Will check out that clutch switch today, as for the questions from weetbix13 the car starts fine always has done, it puffd a cloud of smoke yesterday, but it was the first time it has been run in a couple of months, as i lost my licence and the battery went flat, then i tried to start it and it flooded, but only the one cloud of smoke when it was warm and i gave it a burst , when i can get it to idle it seems fine, same as always, no shaking, maybe a miss or 2 but thats it, , there is no funny smell at idle, and i will have to check the air pump, although it has been unplugged, accouring to the commander my boost is approx .69 of a bar and transition is normal, and is still as fast as ever, although i cant drive till monday as that is when i get my licence back lol, thanks heaps, will keep looking

schwass

I have checked clutch switch, and it seems to be operating fine, goes in and out with the clutch, ............

1QWIK7

iTrader: (33)

If clutch switch checks out, TPS could be the next inexpensive route to take. You have similar problems as me except my car only stalls randonly when car is already warmed up. I have to probably adjust it or i might just replace it.

schwass

think i will get another compression test done, just to check and as not to waste our time, will try and do soon, will post results, thanks mark

spoolage

iTrader: (2)

First off, do you have a boost gauge?

If you do, find out at what RPMS your car makes full boost. After that, put your car in third on the highway and mash the throttle, one you know where full boost is at keep the throttle mashed till redline. While doing this, feel for any point in acceleration where your car feels like it suddenly begins to really make power.

If your car starts making power later on, 5 / 6 your car is probably running rich.

If your car feels like it is breaking up after 6, (you feel the engine isnt pulling nearly as hard as it was initially) your car is probably leaning out.

Either of these things could cause your car to stall, the car running rich would be a definate culprit.

Also, the mileage on your car is pretty ******* high and I would not be surprised if the compression is bad. Make sure who ever is testing the car tests the engine once its cooled down for atleast four or five hours. You dont want to do a compression test while the engine is even remotly warm.

Your mods are intake in origional box, this wont have any effect, BOV and no cat...
I think your engine might be caputz, somone correct me but if I remember correctley the 99 7 has no cat in the mid pipe and if you removed the catylac coverter as well this means you have a pretty free flowing system with a fuel setup that is unable to properly support...

If I am correct in my statement about the car having no cat in the midpipe and you removed your catalytic converter, I would put money down that your engine leaned out, overheated and you probably warped a seal.

Hopes this helps, would like to hear about the results on your second compression test.

schwass

Have just been talking to the guy to book in another compression test, and he was reluctant to do 1, andsaid that if it had low compression then i would notice other things like hard starting..... the car has smooth power all the way no brake ups not nothing, as far as i can remember it has full boost of .69 to .70 of a bar by about 3000 rpm, that is all taken from the commander there is a standard boost gauge in the dash but is a funny reading, will check it out, what do you mean by fuel system not being able to properly support it, do i need a bigger fuel pump or injectors or????? there was only the one cat and as far as i can remember it was in the mid pipe...... but will look as i will be able to tell by where it has been flanged with the replacment pipe the car is running on the base map and this could be causing it to run rich???? and to do with the compression test the last one was done when the car was cool had been parked there over night and was done with the throttle wide open........ hope this helps

schwass

oh and also i always keep an eye on the temperature via the commander as i know that the factory temp gauge is not linear(not sure on the spelling) and have never seen it over 87'c when running, when the motor turns i have turned it back on 5 to 10 mins later and checked the temp and it was up round the 97 98 'c is that too hot?

weetbix13

few things to discuss in this response!

heat soak is ok... it'll come down once the waterpump comes online again.

in the '99 there was only a midpipe-cat i believe as the pre-cat was removed... if that has been replaced with a midpipe it'll be louder and theoretically would run over 0.7BAR due to free flowing system (particularly on 99 spec turbos) but thats an aside.

i'm starting to swing around to the TPS - when did it last drive fine and what has been changed since?

schwass

yeah i thought the heat soak was ok, the boost shouldnt go higher than the .7bar when the boost has been set by the power fc though should it, it never registers any higher. and even the boost gauge on the dash always runs at the same, i will sus out the tps test with a multi meter and see how that looks, thanks heaps for the help.

BobfisH

i have this problem on my '7 too, exactly as he describes. My motor has 110+ psi on both rotors as i only just rebuild it.

Ill check my TPS and also something to check is the wax thermo.

schwass

Have just been researching the thermo wax valve and tps adjusting, it sound like the thermo wax valve will help the idle untill it is warm, but mine still stalls when itis warm, and the tps adjusting, can be done manually, but i have also researched it with the pfc and it sounds like it can be adjusted via that 2, but the only instructions i have for the pfc is foreign, i tried to find an adjustment guide on here but failed, any one know if this can be done?? i will post on the pfc forum as well thanks

weetbix13

do it manually, seriously, it is SO easy.

schwass

hey I have managed to check tps voltages and sensors, all the sensors seem to be working and the voltages are as follows........

the readings that i found on this forum that i read as acceptable values to have your voltages between, are: vta1 open 4.2 - 4.6 vta2 open1.0 - 5.0 vta1 closed .1 - .7 vta2 closed .75 - 1.25.... ok so those were my guidelines my actual reading are as follows,

I got my readings vis the pfc commander
vta1 open 4.5 vta2 open 4.99 vta1 closed .28 ( when i changed the throttle from closed to open and back to closed this reading had changed to .29 and was highlighted... does this mean anything?) vta2 closed .50. so the only reading that i can see that is out and its not by much is the vta2 at .50 when the guidelines seem to want it at .75 - 1.25 . do i need to adjust the tps according to these readings or not???? thanks mark

zonblitz

iTrader: (9)

do you have an aftermaket intake elbow (greddy)?
if you do and you have not plugged off the old hose that goes to stock intake elbow it will cause this... hope this helps you... was my issue after I did pfc changes, tps, slave and master clutch cylinders, clutch switch etc.