SChema

I have a 1988 Turbo II, it starts up fine and idles pretty well too, around 750 to 800 RPM. Once I give it throttle it seems to want to lean out and die, there's absolutely no throttle response too. Every now and then it will allow me to rev up to around 2500 and that's pretty much it. Has anyone else experienced this? I need help!

SChema

I checked my Throttle Positioning Sensor and it has ohmed out right within specifications. I have also checked my exhaust back pressure too.

ddub

How are your injectors working? You say it wants to lean out and die right? Your primary injectors might not be functioning too well.

SChema

I drove it a couple of days ago and it was fine, then it started to hesitate around 20 minutes into the drive, I was in first gear and it revved up slowly.
I took it home and had it neutral, it tried to rev it up, it slowly climbed up to 5000 and then it dropped all the way and my foot was still on full throttle; it's been like that ever since.

iceblue

I know the cold solder joints on the CPU cause it to hesitate like that but its ushaly at 3,800rpm. Are you getting good sprak your wires are good pugs are good timing is on? fule filter is good pump is good and FPR? no vac leaks? if its not these then its the TPS or injectors themselves need cleand or replaced. try unpluging the TPS and see then if its tee tps that will let you know.

SChema

I'm working on the fuel filter right now, I just took the old one off and getting ready to put a new one back on. All the O'Reily's and Autozones are closed already; I'll just have to wait until tomorrow. I've heard somewhere that pretty much all RX-7's, second gens. that I know of, somewhat hesistates at around 3600RPM?, due to the injectors used from factory.

WAYNE88N/A

I'm with dDub- check out your injectors...

If it was a fuel filter, you should be able to rev fine in neutral, but she'd stumble under load. Same with a clogged exhaust...

You checked out the AFM yet?

SChema

I've had the whole exhaust, running just the exhaust side of the turbo and it did the same thing. Once I start it up cold, the motor goes up to 3000RPM and then drops when I hit a the throttle a little. I'm pretty sure the exhaust is not clogged. I've talked to some people and they have said that a car could still idle fine in neutral, but you can't raise the Rpm's at all.

WAYNE88N/A

A REALLY clogged fuel pump inlet filter might do it...

Did this happen all of a sudden, or did it get progressively worse?

SChema

Yeah, it happened all of a sudden. I was driving then I noticed I couldn't go past 5000 RPM in first gear; then I just drove it home. Then I in my garage I tried to take it past 5000, it slowly reach 5000 then dropped to idle and died while the throttle was fully openned. Then again the fuel pump sock filter could be clogged, because I filled the tank about a week before I took it out to drive. I'll check up on that, though the fuel sample I took was pretty clean, probably some bigger debris in the tank.

WAYNE88N/A

Did you start premixing in the last month or so?

SChema

Premixing?
I added some fuel stabilizer to the tank when it was sitting for about 2 months.

vicious525E

old fuel is never good, but i say it would be good to check both your injectors, there might be a easer way, but me and my brother just took off mine, i held them into the fuel rail while he cranked the motor over, this will get alot of gas all over your motor, but it will also give you something to go by, if the injectors arent fireing, check your ecu, if they are, but one seems to fire differently, you need to have at least that one cleaned, but prefferably all. if they all seem to fire week, check your fuel filter, fuel pickup line, blow out both fuel lines, reassemble and check again. if they all seem to work fine, you have fuel pressure (take fuel line off and make sure you have a steady stream of gas comming out, or listen to see if you can hear fuel comming back through the fuel return line, by unbolting your tank cover and listening while someone cranks the car over)
then try new gas, and move on to spark


edit: to test your secondary injectors, you need to ether replace the injectors in your primary fuel rail with the secondarys and repeat test, and/or use a multimeter (dont remember the exact voltage they should get, or amps) and run the car up until the secondary injectors should start (also dont remember the exact rpm)

also, keep in mind, you will be having gas being sprayed on top of a live engine, so, ether use extream care, or dont do it at all, i take no responsability for you or your actions. this is just what we did, and it helped us work out the kinks in my fuel system.

SChema

Yeah, I'm in the process of checking all the fuel components right now. I'm going to replace the fuel filter today and look at the pick up sock in the tank. I've checked my spark already, I have average spark. By the way what's a good and cheap way to increase my spark output? I've looked into the Nology or Accel wires that have built in capacitors to increase spark. I'm just looking for ideas right now.

vicious525E

you can pick up msd 6al's cheep off of ebay. thats what i plan to go with, and a good set of RB wires.

SChema

What about plugs, I'm running NGK's in it right now.