please help , just got my son for his first car 93 turbo , 73k on car and motor , car runs great , driving home from school ,calls me no acceleration , press on the gas it goes but like it not running on all cyl's , it 's running very rich , very , and fuel out the tail pipe , press the gas to the floor , it goes , but very slow , you can feel the turbo's kick in , but very like acceleration , very sugglish, please help .thank you jim robba 93 turbo mazda

 

well the first mistake is you bought him an FD for a first car.

you need to be more specific with your problem, as you are very vague on it.

the are many things that can be wrong... can be as easy as split piping or clogged exhaust, to as expensive as needing a rebuild/new motor.

we need more than just "no acceleration, very sluggish, very rich"

 

to add to the accelaration problem , the car at idle is shaking , this just started , the car was running great no problem , start the car it sounds like crap , there is no cat installed . did replace the plugs , still the same problem , you put your foot into it , it lags big time . maybe valve sticking . oil is good , running very rich , no oil out back end , white smoke out the pipe , like fuell , hurts your eyes , it's like it lost half it's power , it shakes bad at idle , as you get into , it smooths out a like , but power is not there , turbo kick in find . but lags bad , hope this help with the problem . thank you jim

 

what do you mean by split piping please . thank you

 

Two places to start:

1. Boost sensor. Its on the firewall. Make sure the vacuum line didn't pop off.

2. If #1 is fine, next pull the ECU codes: http://www.fd3s.net/engine_codes.html

 

my son added that the oil pressure is running high , around 60 psi , as you put your foot into it , oil pressure goes up. before oil pressure stayed under 60 psi . thank you jim .

 

my oil pressure would get to 100 psi especially if not warm. Do what mahjik said...check the MAP vac line (and all other vac lines just to be sure) and also check for codes.

Trev

 

I think the main problem here is you think the car has pistons and valves...

 

Some one already said it. MAP sensor, MAP sensor, MAP sensor. Your son probably got boost happy and popped the vac hose. Zip tie the hose.

 

This has to be a joke, right? Sticking valve? Not firing on all cylinders?

If this is not a joke, I will try to help you with some bits of personal experience:


At 3,000-4,000 RPM cruising, I normally see 40-60psi on the factory oil gauge. This is not your problem.

You complain of white smoke out of the exhaust, if it is indeed a true chalk white color, it is coolant. Any other colors (blue, gray, black) will be something else.

Listen to Mahjik, if your MAP sensor is electrically disconnected, it will probably fail to even start up. However, the 2 vacuum lines in between the MAP sensor itself and the back of the throttle body are known to pop off under boost.

Your MAP sensor vacuum lines sound to me the likely culprit here. With either of those 2 vacuum lines disconnected, the car will idle violently between 250-1,250 RPM in a bouncy fashion and will dump black smoke at idle and accelleration. Although, when you hit boost at 2,000 RPM (under load) the feeling of the motor will smooth out.

I will have to agree that you made a huge mistake in buying the FD as your son's first car. If you decide to keep it, I hope that you are mechanically nimble and you don't mind your bed time reading becoming your factory shop manual.

 

Honestly, I'd recommend sending the car to a local rotary shop. The 13B-REW (the engine in the FD) is of the engineering that can go from bad to worse if you look at it wrong. Personally, I sprinkle holy water on the hood before I start working on it.

Okay, that last thing is a lie, but seriously, I'd take the car in.

 

The factory service manual states that at 3000 rpms, you should have a minimum of 50 PSI for oil pressure. If the car has been reporting less, most likely the oil pressure sender is either dirty or failing (causing invalid readings intermittently).

The oil pump is driven off the eccentric shaft. Therefor, it will increase proportionally to the rpms.

 

Ill bet you anything he popped the map sensor line. Its beside the brake booster [little black plastic square box with a rubber hose coming out of the bottom]If it pops off it will run shitty.If thats it, put it back on and zip tie it. Just for the record im 40 with a 14 year old son that is drooling over my CYM R1 but its not gonna happen. I personally think that way too much car for your son not to mention if he hits something or another car it will fold up like a beer can. That my friend is the real truth

 

Precisely! typical sticking valves!

 

not kidding big time , sorry this is the first rx7 we bought , but i was trying to compare it to a v8 motor by loos of power , it seems like the power is there , but lags real bad , shakes real bad , you get on it , it just does not have the power there , it's been run like great before this . check the oil it's good , checked the water it's good , the smoke out the back is a fuel smell , running very rich , the pipe tip is black , not oil . i am not kidding at all , sorry for that , thank you for all your help , i am going home to chk asap , my son is missing school , thank you

 

the Map sensor is a likely culprit but have you checked the compression of the engine? Maybe it's just my recent experience with having to rebuild my rotary but 73k on the engine means that it's about that time.



p.s. there's a lot of great rotary shops in our area.. call 'em up and see if they can give it a look over. I just used lucky7racing.net up in El Monte and highly recommend them. Ask for Tony.

 

Well my FD is my first car, I'm also 16 and I think it's a great first car until you fiddle, I always work with my Dad just for safety and experience, as long as the car is well maintained and relatively standard spec, everybody can love it.

Jimrob, sorry to hear abt ur prob, cant give any advice that hasn' been given already.

 

EDIT: I believe this is the MAP sensor...it's been a while
(Red Arrow....also, not my FD)



Check the connections there, both vacuum and electrical

If that's not it...check all the couplers. Could have blown one off or could have a hole in one. Check them all from the turbos (on the left side behind the airbox) to the intake elbow (on the right side by the throttle body). If they're all on correctly, take them off one by one and look for cracks or holes.

 

Yep, that's the map sensor. Make sure it's connected and the line's not leaking or anything.

I strongly recommend that you take the car to a rotary specialist and have them look it over from top to bottom. The mention of 'full exhaust' is a little scary - first, because it's going to require some gymnastics to pass cali emissions. Second, because low-restriction exhausts cause major increases in boost, and major increases in boost will blow the motor if not handled properly. A rotary specialist will check over everything. Dealers and regular performance shops simply can't do anything good with these cars. The turbo system and rotary engine is just too far out of their expereince.

Take a look through the FAQ here, particularly in the "Buying an RX-7" topics. As a new owner new to this type of car it should be very helpful, regardless of your mechanical experience.

Dave

 

thank you, you guys are great , checked the map sensor ,no luck all hooked up , one vac line to it and elec connector ,remove connector ,car wouldn't start, installed it starts, looking over all vac lines today . remove aft bottom plug, turned engine over , it sounded good , like a compresser,will need to get to front bottom plug by under the car , have to go to work . noted a little fuel smell and blue to black smoke out tail pipe , not oil .to chk vac line can you on this use carb cleaner . any good shop in downey ca. reguards jim robba

 

"No cat," shaking at idle, and no power...

Check out all the stuff everyone else said, but it may be that excessive boost caused by the free-flowing exhaust has caused detonation and resulted in a blown apex seal.

To determine the engine condition, you need to do (or get someone to do) a compression check. There are lots of threads referencing checking compression. If that checks out, then you are looking for more minor stuff. If it doesn't, then you'll need a rebuild.

 

Yeah, I was being optimistic about that since the map sensor hadn't been checked.

Now it's really time for that rotary shop. I would get the compression test done there unless the rotary shop is royally inconvenient. In which case the Mazda dealer can do the compression test. (If it fails compression, you will still need to go to the rotary shop for repair - Mazda's probably not the best value on this item).

 

the cat has been off the car for 1 year , has a hks tip on it , it didn't have any problem before this , plus this happen on the street around my house , car has been doing 20 mph on side streets . i don't think the cat has any thing to do with it . my son removed the air box to chk vac lines , can you run the car with the air box remove .also would bad turbo's make the car run ruff, like the problem we have . car running very rich , black smoke and black exhaust tip. also with the engine shaking i could hear a ticking from the engine if this helps . thanks jim

 

with the map sensor , maybe it's bad itself . with elec plug removed the car will not start, the vac hose is connected and goes to the throttle body only one hose as i see, maybe the map is bad inside the map box , any way to chk it itself . alot sounds like it's the map sensor , the vac hose look new , all the hose look new , very good condition , we are still checking all hoses , will chk front bottom plug tomorrow , did chk rear bottom plug , removed and turned engine over very loud compressor sounds , it would blow you finger off. help me , thanks

 

what should compression be on this motor , can any one help with this test please , will go out and buy a gauge or set up to do this test , my son is 18 , and he's doing all the work which is learning the car . thank you sirs