smnc

Well, the car is all back together and running again.

Clean injectors, cleaned intake, cleaned K&N airfilter, electrical connections cleaned and a bit of di-electric grease, and all vaccum hoses replaced.

Unfortunately, she still has the same miss and idle problems as before. And the soleniods are still going crazy.
At least she runs now.

I'm going to replace the fuel pump next week, and the in-tank filter (which I didn't have time to do this week).

I also still have to install my grounding kit (more about that in another thread).

Anyone have any other thoughts on my problem?

https://www.rx7club.com/showthread.p...hreadid=282433

mazda123x5

Well Iam no expert but could it be a bad tps? or just not
adjusted right. when I have set my tps if its out of wack
one of the soleniods starts clicking like crazy.

smnc

Really? I'll try that...

smnc

Well, after dinking with the TPS, I've come to the conclusion that it's FUBAR...

So looks like I'll be pulling the TPS off my parts car...

mazda123x5

You can check It with an ohm meter just to make sure.
When I was setting mine I wanted to make sure it was
o.k. it checked out fine, one less thing to worry about.

MarkPerez

I'm right with you ,man. i'm still trying,, i idle fine though
@850 rpms and smooth,, spin it up,, starts to miss. my
soleniods don't go nuts either... and one night i parked the car, next day ran like crap... and still doing it.. i'm thinking something electrical/valve/soleniod.. my last ditch effort goes straight to the ECU. and then still don't want to straighten out, then it's .357 magnum,,,baby.

i think,, hhmmmm this car 'was' dead and i brought it back from the dead.... dawn of the dead,,****,****..
my -SE is the rolling dead. no wonder it don't run right.

Ha Ha

smnc

Sound like you're having a rough time of it MarkPerez... a few thoughts...
1.) How's your grounds? I used my voltmeter to check from the + battery terminal to my firewall, engine, strut towers... My old car had crappy grounds that gave me fuel pump problems...
2.) Have you checked the in-tank fuel filter? It's a sort of strainer at the bottom of the fuel pick-up
3.) Did you check the voltage at the fuel pump hook-up?
4.) Vaccum hoses and soleniods are a possibillity... Takes about a day to do them all... not that hard...
5.) Sounds dumb, but did you check your TPS?

LongDuck

TPS can account for all kinds of idle problems, because the signal that it produces is sent to the ECU for combination with other data to determine how much fuel should flow. An off-idle miss is likely due to one of the many sensors out there that affects fuel injection, but could also be vacuum advance on the dizzy, or even a vacuum line that's causing a vacuum leak to one of your solenoids.

The place to start is to rig up the test light apparatus and plug it in and get it tuned to idle well. An 850rpm idle isn't bad at all on an SE. Mine idles at 800, but jumps around up to 900, up to 1000 sometimes based on how hot out it is, how much electrical load I'm pulling, and whether or not it feels like cooperating...

The TPS is a quick an easy fix at 2x10mm bolts, too.

smnc

Yup... the replacement TPS goes on in the morning....

My idle is already good at 800rpm... at least until the TPS goes out after the car warms up.

Then my idle fluctuates 500-1100 rpm.

I'll post how it turns out...

MarkPerez

No you guys, remember it ran fine,oh wait...... these things go out of whack on a whim don't they ? there are so many things in the chain, it's like the car made up it's mind to **** me off.. really !! i'm pretty wise about rx7's. but this EFI is a challenge. it all has to work right or it won't work at all... i'll refresh the story about this -SE. i bought it from an ex girlfriends brother for $150.00.
He said it had overheated and steam came out the tailpipes, so he parked it ,had another car so he blew it off for 6 years.it sat for 6 years untill i bought it.put a battery in it and it turned over,cool,. so now i have an 84
-SE. drained the gas tank first and crap came out,, droped the tank, opened it up. the strainer was melted
kinda,pick-up tubes, pluged,,cleaned the tank,pick-ups, fuel level guage,replaced all the hi-presure hoses, replaced all the hoses except the hardlines. but i blew those out with compressed air. replaced the fuel pump, fuel filter and added an extra fuel filter fromthe hardline
to the delivery pipe. test the system and theres mass fuel presure, hook it all up.. then i had to clean the entire cooling system to do the CRC block weld treatment. new hoses,etc,,,cooling system. the engine must run to do the treatment. the thing fired right up on the first try, did all the block weld requirements and the block weld treatment took...it worked. of coarse i did all the tune up stuff, oil change,etc. and the thing runs/ran
perfect. doesn't get hot, 6th ports work great, So i start driving the car,, start to drive it more and more. The paint is gone but the whole car works fine. after owning/driving a 1982 GS, then a 84 -SE i can tell you that a 82 handles like a go-kart and the 84 handles like a rx7.. i park the car one night, the next day it ran like crap,,,still the exact same problem. the things i can test
(tps) for one all test good, and are set right. i haven't replaced any vacum hose though.. the car was dead
and it's a good car.

gsl-se addict

iTrader: (3)

Mark,

How is your fuel pressure? Did you check the water thermo sensor? How about the voltages on the ecu? You can also rig up a little test light to check for codes on the ecu. I did it to mine, and I found the the AFM was acting up. If you want to know how, let me know. I will try to write some sort of write-up on it. The se ecu, as you know is pretty simplistic. I believe that it only shows about 6 different codes.

Kent

GavinJuice

I'm interested in finding if i have any codes, i have a bit of a miss at idle, but i al so have a fantastic leaky exhaust which might account for that.

LongDuck

Mark - in your explanation, you noted that you installed a new, separate fuel filter between the hard line and the feed. This may be the cause of some of your problems.

The SE's have very high fuel pressure to feed the EFI system, so if you installed a standard 'carb' fuel filter, it will be too restrictive to flow and could cause idle and mixture problems. The reason for this is that the cheap, plastic standard fuel filters cannot handle the high volume and pressure requirements of an EFI system. If you recall, your SE has a huge (4"-8" cylinder) fuel filter by the fuel pump which is secured by hard attachments to the fuel pump and hardlines. This is because it takes a big filter (and metal) to contain the pressures that EFI fuel systems require to run correctly.

If you've installed an in-between fuel filter - take it out. The SE doesn't need it, and it will only cause problems. Reply back if you're able to do this and retest the car. HTH,

MarkPerez

Longduck. i hear you.. the engine starts,has been running with the extra fuel filter.. yeah bought a new -SE fuel filter ( $$$$$) @ the pump, and added a metal can,hi-presure, low restrictive in-line fuel filter.remember
i had to clean out the gas tank, and though i cleaned it the best i could i added the extra filter just in case. with
all the info from around the net plus the books i have.
i have covered just about everything. as far as the fuel
system goes it's primo.i have replaced the ecu awhile back too. new plugs lately, never touched the timing,
(i know better)the same goes for the TPS. @ idle it's 850 rpm,,rock solid !! no ups,or downs,,850(real good)
smooth and even. everythings hitting. spin it up to 2500 rpms and hold it there, it starts to miss, spin it up to 3500 rpms and hold it, it starts missing more and feels rough. back off the gas. goes right back to 850. not 1000, not 700 rpms. right to 850 and idles smooth and even. and i'm in san diego(good weather)

yeah man.. i'll check out whatever you write up. i have tons of how-tos for rx7's and -SE's = rotory engines
i've gone as far as emailing jesse james from WCC
asking what he thought among other hi-profile grease monkeys...lol what'ch-ya-got ??? i'm open to all input.

LongDuck

Injectors? The reason why I say this is that if your car will idle at 850 rock-steady, and only seems to 'miss' at high rpm then you could be exceeding the maximum flow of one or both of your injectors, resulting in a lean mixture (which causes hunting or missing). If the injector is clogged, it won't be able to flow correctly, and will 'top-out' at less than the pulse width for fuel flow at higher rpm's.

The only other thing that I'd recommend is to take another look at your Distributor Cap and Rotor and look for cracks or high tension lines that run side-by-side - this can result in cross-talk that could cause a high rpm miss. Check your coil leads to the dizzy, as well.

Since it idles so smoothly, this is certainly not a run-of-the-mill issue to troubleshoot.

smnc

Yeah, unlike my problem that involves rough idle as well...

So my problem has been getting progressivly worse. This morning, my engine started cutting out at 3k and dropping back to idle (1500 rpm today)... Even under 3k, it was running horrible, but idled well (as well as it gets these days anyway)...

Made the car completely undriveable.

Again, I was getting all kinds of wonky readings from my TPS (the 2nd one).

Finally in desperation, I unplugged the TPS.

Car runs almost perfect up to 4k now.

Stills idles rough, but no more miss until 4k. Then she misses like mad, but I'm guessing that's because I have no TPS now?

Sigh!

So I guess the 2nd TPS is bad too?
Or my ECU is FUBAR...

I'm starting to think of just trashing the stock system and getting an aftermarket ECU.
I was planning on it eventually anyways, but this might move things up a bit...

JIMMY54

iTrader: (2)

I'll pm you in a sec!

LongDuck

The TPS is more likely to be the problem than the ECU. The 1st Gen SE's did not have problems with electronics like some of the 2nd Gen cars. If you end up going to a microtech, megasquirt or some other system, be sure to SAVE your stock ECU - it is worth money to those of us out here that have SE's.

I already have a spare N304 ECU for my SE, but don't just throw parts like that away - the dealer would be asking over a $1000 for that part, alone.

Get a new TPS for $140 (Mazdatrix) and give it a shot - the TPS is almost certainly bad based on your symptoms.