paulagre

Starts up fine, idles high at 1000 once its warm. oxygen sensor reads .1v and after revving it, it climbs up until settling at .7v and idling at that. it has a very unstead misfire, until smoothing out. Then if you rev it, it has a huge hesitation...the faster you hit the throttle the more of a choking hesitation it has. It almost dies when you hit the throttle, but then it revs up. and if I rev it up to say 4,000rpms plus, it is very slow to return to idle.

Map sensor reads 1.3v from A - GND at idle (which is at 17inches) and then revving it real fast to 0 inches it shows 2.5v. which appears to be exactly normal.

TPS is reading correctly as well, throughout both ranges.

So its rich, way rich. But why? Leaking injector?

paulagre

I feel like this guy /\

Sending out the vibe to the smart guys!!!

fazdaRX_8

sounds formilure

RotaryEvolution

iTrader: (30)

way to revive a 5 year old thread...

the spelling ***** will be here in a minute so stay put.

fazdaRX_8

Sorry I am searching through the threads to solve my issues, and my post count was down so I posted LoL

maybe I will just steal this thread

93 FD
I have done a whole bunch of things to it recently including cooling mods, and a second oil cooler, the car ran fine for the longest time, but then I took it on a trip about 225 miles there

well on a downhill decelerating all the sudden I get misfires
from then on I got misfires and even stalling issues

on location I changed out my leading spark plugs, it ran better but man she wasn't happy, I towed her home

today I found that the TPS clip was broken and a wire (bottom black one) was completely broken, So i found some new plugs at the wrecking yard, soldered them in, I also replaced the trailing plugs

the car again runs better but still has misfires at idle, and when holding a rev say 3000 rpms it misfires randomly and drops rpms to 2800 and fumbles around there.

I tested TPS voltage thinking perhaps the TPS shorted out, well all the bottom wire seems to be in spec, but the second wire is 1.34 and 4.99 acceptable range should be 1.0-1.2 and 4.8-5.0 so I thought maybe I could adjust TPS but then again the idle screw is set so if i set that to 0 then my lower range would probably be within spec

seems to be around 15-16 vacuum

compression test for both rotors where good

really at a lost, thinking a vacuum leak which it just doesn't feel like.

Leaking fuel injector?
bad 02 sensor?
bad coils?

fazdaRX_8

found a thread suggesting fuel filter?

fazdaRX_8

bump

RotaryEvolution

iTrader: (30)

start with general maintenance points, fuel filter, fresh fuel, spark plugs, plug wires and air filter.

the symptoms given are difficult for a non hands on approach, ie technical assistance will all be random guesses. could be clogged exhaust, could be damaged internal engine components, could be fuel related either rich or lean, could be a massive vacuum leak, could be a lot of things. easiest start point is doing a compression test of the engine to verify it's condition.

Jeff5808

iTrader: (7)

Is the check engine light on?

fazdaRX_8

CEL is not on,

compression check showed about 90 psi on both rotors at room tempreature, 120 peak in rear 115 peak in front

Ordered a new fuel filter just cuz, but it was replaced about 3k miles ago by a petit one.
Ordered a new 02 sensor as well

all new spark plugs and wires.

I was hoping someone might seen an obvious awnser to my issues, I mean I can't be the only one with them, again I searched fround many threads but non where the op came back with what they found or if the fixed.

Jeff5808

iTrader: (7)

Maybe the map sensor is faulty? Check F-167 in the manual for testing procedures.