eudaxia

iTrader: (1)

Hello all,

I picked up my car in Florida this summer from a guy who had barely driven it for a year. I took it to Jeff at Maztech in Tampa, FL (excellent mechanic) and he regrounded it and adjusted the idle slightly because it was stalling at times in the hot weather. This fixed the problem for the most part but now it only stalls intermittently with the ac on.

After coming back up to DC for school, I noticed that the fuel economy suddenly dropped and excessive white smoke coming out from the exhaust. I first thought it was due to all my city driving but 150 miles per tank is a little low. I replaced the fuel filter which did absolutely nothing and am now thinking of replacing the 02 sensor.

However, since I bought the car I've always felt that it was laboring to start, as if it were always kind of halfway flooded. The past couple of days it has flooded twice and I really want to fix this problem before it gets more annoying. Yanking out that fuse in the cold rain this morning was not fun.

1) bad fuel economy had an acute onset
2) no check engine light
3) labored starting existed before bad fuel economy started

I have no boost gauge (no comments ramy) but the car runs fine once it gets started. The research I've done on the forum seems to indicate that it may be a bad FPR or MAP sensor. Does anyone have any experience in dealing with the same set of problems? I wanted to get an opinion before I start spending money and time on things that don't need to be replaced. Joseph

Sonny

Welcome aboard!

If you're having trouble with hot starts and you're blowing smoke, you might want to do a more basic engine health test: the compression test. You'll need a rotary specific compression tester to get the best results. The Mazda dealership can do it for you but most rotary specific shops have a tester, too.

How many miles are on it? Your hot start problems and excessive fuel consumption can also be attributed to leaking fuel injectors. That's not an uncommon problem with high mileage injectors. Mine were in pretty awful shape when I got my car, but after getting them cleaned, my mpg jumped from about 13 mpg (avg) to about 20 mpg (avg).

Do the compression test first though. It's the best way to find out the overall health of the engine.


Sonny

adam c

iTrader: (2)

Your fuel economy isn't abnormal for all "around town" driving. I get 9-10 mpg with that type of driving.

A search on "flooding" will probably yield you some good results.

dubulup

could be coolant seals are letting coolant into the combustion chamber...hard cold starts...seems flooded...white smoke. Fuel smoke is black.

Bad MPG, could be the O2...or a heavy right foot

RC engineering gives RX7club members 10% discount on clean/cal/bal service ~$120

Sonny

I think you've got dirty injectors, Adam. Do the hose job so that you can clean the injectors, too. I know you want to.

Sonny

FDNewbie

iTrader: (10)

Joseph, I think that's one very big possibility, ESP. since you don't have a boost gauge (ahem ahem). I'm tellin you man...you'd be surprised how often you're boosting during regular driving...the sequential system allows the primary turbo to come online at very low rpms (2500rpm), and takes very little throttle effort to spool.

So...in response to ...nuff said

Oh and Sonny, his FD only has 67K miles...so it's def. not high mileage at all.

EDIT: Joseph, I just HAD to say this: Congrats on your FIRST POST, given you've been on the forum for YEARS lol

Snook

iTrader: (12)

WOW you were lucky to go to Jeff at Maztech! He's great huh I'm in love with the guy. I don't think you can get a more honest and fair priced mechanic and he knows so much being there for 35 years!

About your problem I think leaking injector is possible. How high does it idle?

-Yanni

eudaxia

iTrader: (1)

Thank you all for the advice. With regards to the injectors, i've run techron concentrate in it a couple of times since I got it. I'm not sure if the chemical cleaning is good enough but again, the problem seems to have come on acutely and i'd think clogged injectors would be a slow-onset sort of thing. Jeff at Maztech is an excellent mechanic, I drove across the state to have him check out my car before bringing it up to DC. He told me that the compression was fine. Also, I think that poor compression causes stalling and white smoke all the time, not just during starts. My heavy right foot or the O2 sensor are also possibilities, but the main problem seems to be the labored starting and flooding which I thought were somehow related. If it was the injectors, is there any product out there that would improve it? I don't really want to take them apart. --joseph

adam c

iTrader: (2)

BG44K is a very strong injector cleaner that works very well.

alberto_mg

I hope that is for all 4. Marren in CT also does them for ~$35 each.

IF its injectors, I hope you have a garage to store the car while its down other wise you might want to find a good shop in your area. Check the regional forums.

Also, I hope you've made parking provisions for when it snows down there...

FDNewbie

iTrader: (10)

Yea I got him covered there

Csefiroth0

get the gauges bro

switch

We do them for $12 each.... Same service, just lower cost.

Gordon
WitchHunter Performance