mazdaverx713b

iTrader: (91)

i was diagnosing some problems with my 10AE tonight and trying to get it to start. the last time it started it really felt like it was running on one rotor. very sluggish to rev and whatnot, basiaclly no power. so i cranked her over for a few seconds and smelled the flooded fuel smell(you guys know that smell) and decided to pull the plugs. the rear rotor's plugs were fairly wet and the front rotor's plugs were bone dry, just some carbon deposits. hmmm, so i pulled the 30A and 40A fuses on the block and cranked again, hoping to push the remainder of the gas out of the housings. i pushed some more gas out of the rear housing and the front housing was bone dry. i reinstalled the fuses nad cranked again. wet rear dry front. what could be going on here? bad injector resistor pack? i am lost. why wouldnt the front rotor be getting any gas? any help would be very appreciated

Whizbang

check to see if the primary injector on the front rotor is in operating condition.

1) Check connector to the injector
2) check resistance of injector with DMM. I know low impedance injectors should be within 1.5 to 3 ohms. Not sure about High impedance like you have.
3) see if injector is clicking while cranking the car. This is tricky because the injector is hard to see to. BUt use a screwdriver and hold the handle near your ear with the tip on the injector. Dont get hit by moving stuff.

mazdaverx713b

iTrader: (91)

i'll check that tomorrow. i think its gonna be trick to get at the injector

mazdaverx713b

iTrader: (91)

if i cant find anything there, are there any other places i should look?

mazdaverx713b

iTrader: (91)

do you guys think it could be a bad resistor pack?

Whizbang

you could check resistance of the resistor pack...wait isnt this an 88? should it be high impedance (ie no resistor pack)

mazdaverx713b

iTrader: (91)

yeah, its an 88. i'm kinda new to the turbo II, so this is going to require my patience. it is however my 15th RX-7, so i am not afraid to work to find this problem. i just need to know possible causes of this problem.

Whizbang

15th? damn.

well although i thought where was no resistor pack on the 87.5+, you could check and compare resistances of the four connections.

RoFLCoPTeR

i have the same problem with my car right now. we diagnosed the problem as fouled fuel injectors. i think just for the safety of it all i would take out all of the injectors, give them a quick one over and get them professional cleaned(30 bucks around where i live). i have to do the exact same thing to my car. front dry, back wet. mine is a 1987 gxl 6 port n/a. hope this helps.

mazdaverx713b

iTrader: (91)

i wonder if i can test the pulses at the ecu to see if the injectors are firing. i also have some noid lights... would it be helpful to pull them, run them on the bench to see how they flow. i have an extra pump, some wiring and i could go get some gas....

mazdaverx713b

iTrader: (91)

i did want to ask, how did you come to the conclusion that the injectors are "fouled"?

Whizbang

perhaps he meant "clogged"

go to witchhunter's site (youll have to google it) they explain how to tell if an injector is bad. good read.

mazdaverx713b

iTrader: (91)

thats a good site! good price and a fast turn around time. i just want to make sure that could be a possible reason as to why i'm not getting gas to the front rotor before i go tearing into it.

HAILERS

Should not be a resistor pack on a 88.

Pull the intake off. Unbolt the primary fuel rail. Leave the electrical plugs on the injectors and then zip tie the injectors to the rail.

Jumper the fuel pump check connector and turn the key to ON.

Pull the CAS out but leave its electrical plug on. Spin the CAS bottom gear with the above conditions. The injectors should spit fuel when you spin the CAS lower gear.

One spits and the other does not?? Swap electrical connectors and do it again.

Before doing that, go to the ECU and the applicable wire for the primary injector your interested in. Leave the plugs on the ECU and backprobe the wire for the injector your interested in. Key to ON. You should see battery voltage,. proving the electrical circuit from the battery....to Main Relay ......to the injector..........to the ECU plug is good for that injector.

Make sense? Did to me anyway.

On 88's the resistance is built into the injector so you don't need a resistor package that WAS located on the fender below the afm/airbox on early 87.

mazdaverx713b

iTrader: (91)

so, when probing, am i testing for voltage to open the injectors? if one spits and the other does not, does that mean bad injector or bad plug? the description i got from the previous owner is that he was driving the car, it got a little louder. when he went to take off from a stop there was no power and it wwas running short on power. i was able to start the car and move it around and it was running on one rotor. it stalled and has yet to start again. just figured i'd throw that in to see if it may help.

mazdaverx713b

iTrader: (91)

i'll start checking stuff tomorrow

HAILERS

Your backprobing the injector wire at the ECU to see IF there is 12vdc there or not. That's all. No voltage, then you've a broken connection b/t the injector and the ECU.

IF you spin the CAS and are looking at the two injectors, they should both spit fuel when their turn comes up. If no fuel comes out of one of them, then get a meter out and see if there is 12v available at that injectors plug or not. Got 12v? Then go to the ECU and see if there is 12c there at the wire for that injector.

Got 12v both places? Then swap injector plugs from one primary to the other and try again. IF it now spits fuel, then the injector is good but there is something wrong on the ECU side of things. If fact, if one injector does not spit fuel when you spin the CAS, that is the moment you should swap injector plugs and try again to determine if the it's the injector or the ECU.

I suppose a noid light at the injector might help determine if the injector is pulsing or not. Never done that myself. A meter backprobing the injector wire at the ECU won't show much but if voltage is there or not.

Actually, if the key were to ON and the small plug was OFF the ECU, you could MOMENTARILY touch/short the wire to a given injector and make it pulse. Not recommended for more than a second or so, just to see if it clicks

Say you find that one injector does not pulse when you do what I wrote above. You could go to the ECU and pull the small plug off and go to that injectors wire at the PLUG, and put a gnd on that wire with the key to ON. It should click if you do that and if fuel pressure is in the rail it should flow fuel.

I mention spinning the cas in the above post because that is how the car works in real life and you don't have some plugs off, some plugs on etc. Plus you can visually see if the injector is spraying or not spraying

There's a half dozen ways to see if the injector is working or not. Actually more.

mazdaverx713b

iTrader: (91)

thats an awesome write up! i'll definatly get into it today. thank you.