sbrx7

Hey gang,

I just finished repacing or cleaning everything in my fuel system and still can't get the engine to pull past 4500 RPM. Background: Bought the car with a fuel tank full of water, and rust. Replaced tank, serviced injectors, flushed out fuel lines, replaced filter. Compression numbers were very good. I have sprayed around the intake, upper and lower, looking for a vacuum leak, verified fuel pressure, and pulled out what few hairs I have left. The car is driveable and does idle much better now, but any RPM past 4500 or so aren't much good, and any throttle opening past about 5/8 isn't much good either. In other words, I can drive it, but can't have any fun in it!! Any more ideas where to look? Sensors I can test? I have a lot to do to this car before it's really nice, but don't want to fix any of that before it runs right.

Thanks in advance!!!!

Steve Bertok
94 MB touring
85 GSL-SE (sick, still!)

Serzy

I know nothin about GSL-SE's but I sure can sling words around The gas tanks on our cars have a drain plug so maybe its a good idea to chk that again, chk the fuel filter again, theres always stuff that gets left behind even after a good cleaning. Try the TPS (Throttle Position Sensor) also try the O2 sensor and maybe your fuel pump is goin bad? But im not sure on the last one if thats so much a problem with the gsl-se's as it can be with the 12a first gens.

davo22

al right everything is connected. this 4500 specific sounds odd. Have you looked into the ignition and it's components. Have you adjusted the Throttle postion sensor. Even a poorly running motor should rev above 4500. we are talking free revs correct. If you are talking under load I would consider checking your timing and ignitors. When I first placed an MSD on my car I could not get the car to rev above 4500, however the problem had to do with having the leading & trialing wires mixed & 1 & 2 mixed. So it sounds like igntion. also beware of any loud popping coming from the motor when you jab the throttle, this is igniting the incoming mixture, very bad. If you already knew alll this sorry to ramble on.
lates
davo

sbrx7

Let me clarify a bit guys. The car will rev to redline, free revs, but takes a long time getting there, sputtering the whole way (4500 up). On the street, under a load, it just isn't worth it. It'll get to red line, but takes it's time. The gas in the newly replaced take was fresh from the pump, so I'm sure it's clean. The pump should be OK, it has been tested for pressure, perhaps a shade low, but very much within specs. That was before the tank repalcement too. All of the ignition components are new (cap, wires, plugs) I'm going to look into vacuum advance items, and perhaps cat. converter issues this week. Anything I've missed?

Thanks again!!!
SB

Audio Science

I'm having the same exact problem with my 12a. At 4500 it just starts like missing really bad eh? And it will make it upto 7k but it takes forever. I think my problem is my distributor being off a tooth. I'm going to adjust that tomarrow and see what happens. Maybe we have the same prob. Does yours do it in second gear as well? Mine just does it in 1st. 2nd through 5th are fine as far as they don't miss at all they just don't seem to have much power.

DONNA

Hi, I may be out of turn but could there be a chance that your exhaust is stoped or stopping up, i had a cat go bad b4 and it drove as if i were towing a house trailer bhind me,,just my 2 cents......good luck,,,,,,

Denny

I agree with Donna....If you've had a fuel tank full of water!?!? You may well have a messed up cat converter. Classic sign of clogged/broken cat is car won't perform under load, especially trying to get to high revs.

Best to yuh...
Denny, from the 'ol corncrib...

sbrx7

I think I better drop the exhaust and take a peek at the ol' converter. The car is way off on power, and no, it's not just cause I'm used to my third gen's 320 HP. I know the first gen is a different animal, but heck, it can barely turn the tires over. I haven't looked yet, does this car have two converters on it like the 3rd gen? IF it only has one, I guess I can break the exhaust apart there and see if the car will rev up better. Of course, the neighboors won't have the same appreciation for an uncorked rotary we all do, too bad While we are on the subject, if it turns out to be the cat, what are the recommendations to replace it? I imagine RB has some trick exhaust setup, with a trick price. I know you have to maintain some back pressure to keep the 6 port setup functioning properly.

BTW, the tank full of water was courtesy of the previous owner being too lazy or cheap to spend 5 bucks on a fuel cap and using a friggin' SOCK instead. Between that, some minimal body damage and an interior full of dog hair, I don't think he deserved to own the car anymore.....there, there little 7, it'll be OK

rx7gslse

I had the same issue (well, about 5500prm) a few months back.. It was a clogged cat in my case. Changing that made a world of difference. FYI, in stock format this car has 3 cats, 2 pre-cats and a main. They can be purchased individually from mazdatrix at something like 400$ apeice. The main cat is most likely the cause..

That being said, by far the way to go is to get a Bonez cat from rx7.com. I got mine ($250) and it is an easy bolt on that replaces all 3 cats, and then passed emissions here in DFW with flying colors. It was an entirly different animal afterwards. As a suggestion, I would also replace you o2 sensor along with it. Simple cheap fix and will probably keep you from fouling your new cat as quickly. If you read back a few months you will see many posts raving about the Bonez also..

That's my $.02 for Wednesday.

JIMMY54

iTrader: (2)

I had that problem a while back on my -se also. It wouldn't stay at a steady rev and had no power. Near the RE-EGI box on the drivers side , there should be 2 plugs. a green and orange i belive. Once i unplugged them the car ran perfect and since then i have never plugged them back in and the car passed emissions like that too, so i have no idea what the **** they did!
Since this was a bit back, and i am too lazy to go look lol , I think i put a piece of speaker wire from one conection to the other one. NOT on the plugs but where they are supposed to go into.

If the car doesn't start without the plugs in put the speaker wire there.... but before doing that try it without the wire in place.