adrian034

Hi everyone, new to the forum / rx7. I got a 85 gsl-se (13b fuel injection) couple months ago. Car always feel like it has only 80 horsepower. The car starts fine and everything is ok. I changed oil and air filter. Was wondering what to check for with power lost on the GSL-SE. I searched and only found info on 12a carb engines. Any ideas would be appreciated. Thanks!
Adrian

74RX4

iTrader: (10)

Make sure the plug wires are on the correct plugs. Ones from distributor terminals marked T1 and T2 go to the top plugs. Ones marked L1 and L2 go to lower plugs. 1 is front 2 is rear.
If they are on correctly....

13B....Spark plugs, distributor cap and rotor. If no change after those items, replace the fuel filter.

For others with a 12A....Make sure your throttle return is connected correctly (search for tetter totter).
Replace fuel filter, spark plugs, distributor cap and rotor.

Only a different order because the 13B fuel filter is much more expensive and more of a hassle to change.

Rx-7Doctor

iTrader: (13)

Adrian,

There are only a few differences when diagnosing for a power loss between the two.

What applies to both are the following..

Compression- Have to have good compression in both housings. (procedure to check is in the archives)

Spark. Have to have spark to the leading side. Check to make sure you have spark to both leading plugs. This can be tested with a timing light or a in line spark plug tester and of course the old fashioned way of grounding the plug.

Restriction in the Exhaust. IE: Clogged or internally broken catalytic converter.

Variety of vacuum leaks.

Poor fuel pressure and or volume. Can be tested, Procedure in Haynes or FSM

Air filter restricted- (you already changed but mentioning for reference.)

Timing off- Need to check with light. Specs and procedure in Haynes or FSM.



Gsl-Se specific-

TPS defective or not set properly. Procedure in Haynes or FSM

1 injector not operating- Usually caused by deterioration of the connector and losing a ground.
Can be found by performing ECU pin test. Procedure in Haynes or FSM

EGI fuse at fusible link block bad.

Other less common. Download a copy of your FSM . You can view the FSM by copying and pasting the link in my signature. Then go to the section for trouble shooting.

adrian034

thanks so much for the info. I will check all these things. great forum!

wilme2

I have a wierd and more serious problem. Power runs fine when cold, but when you shut it off after driving, it only restarts with what feels like about 40 horsepower. Let is sit overnight and it runs fine again - until you shut it off and try to restart...

snwyvern

Try removing your fuel filler cap.

mikeric

iTrader: (20)

Your fuel pump may be overheating or your cat may be clogged and expanding when hot minimizing the airflow.

LongDuck

To the OP - is your SE like this *all* the time, or does it only have reduced power under certain conditions?

I've experienced reduced power on several occasions, and they were all intermittent and found through typical troubleshooting procedures for fuel and spark.

One of the intricacies of the SE's is the function of the Air Flow Meter (AFM) which is used to tell the ECU how much air the engine is bringing in, and thusly, how much fuel should be injected (increased pulse width) to be balanced. If your AFM is malfunctioning, it could lead to poor performance.

Lastly, what are your fuel mileage estimates? That would tell us a lot, also.

adrian034

its only getting about 16-18 mpg.

thunkrd

iTrader: (1)

16-18 sounds pretty normal, considering most rx7 owners mash a lot.

mine has a power loss issue sometimes, but i think it's related to my MSD, anyway it's ignition related... or its my aux ports. I want to take my injectors to be cleaned.

adrian, hope you can get it running better. maybe you should clean the contacts for the ignitors and other things related to the ignition.

LongDuck

Someone else may have mentioned it, but I found an intermittent loss of power (search: 'running on one rotor') to be caused by a deteriorated fuel injector pigtail at the wiring harness. When the engine would heat up, it would stretch the harness and cause the wires to pull apart to the leading chamber - shutting down that injector, hence the 'running-on-one-rotor' symptom.

I found this by warming up the engine and then moving the wiring harnesses around until I could replicate the problem. Sure enough, it was the fuel injector pigtail. Replaced them both with Borg-Warner parts at $8 each, and has been 100% ever since.

It could be something like that, though standard 'tune-up' rules would apply here as well; air filter, fuel filter ($$$ for SE's), plugs, cap, rotor, and plug wires, oil change, and check your belts and hoses.

For MPG - 16-18 is about right for mostly city driving on an SE. If the mileage were way up, I'd suspect injectors, or fuel flow; if way down (12-13mpg), I'd suspect ignition, air flow meter, air filter, or internal engine wear (apex seals, side seals).

adrian034

Thanks again for all the great advise. I will try things listed above (cheapest first). I think most of these parts need to be replaced anyways since its a old car. By the way, how can you tell if the apex seals or side seals is worn? I am getting some start up smoke in the morning now. But only first thing in the morning. Also, any way to test AFM is functioning properly?

gsl-se addict

iTrader: (3)

Download the FSM from here:
http://foxed.ca/foxed/index.php?page=rx7manual

As others have mentioned, it could be several things. A clogged fuel filter or clogged cat would probably be the 1st things to check. I assume that your leading ignition is okay (check anyway) as without leading, the engine will run poorly and be way down on power. Check the condition of the spark plugs while you are at it. Only replace with the correct NGK or Denso plugs. The incorrect plug (autolite, etc.) can stick too far into the chamber and chip the apex seals.

Just like any other problem on the car, you will have to check things one-by-one until you find the problem. It is a good experience to do it like this. Troubleshooting is 90% of automotive mechanic work. Once you find the problem, you know what you need to do to fix it. Most shops do not follow this practice and just replace every part that it could be (at your expense) until the problem goes away. This is a poor practice in my book.

Rx-7Doctor

iTrader: (13)

When in doubt check post #3!

I have already given you the check list?

Now don't post up until you have checked the basics that I have and others posted. :-)