my rx7 is fucked up and i dont know what it is. i only drive like a block and it starts bogging down and then eventually turns off and i have to wait about 15 min. for it to start up again. just too do it all over again i have already changed the fuel filter and the fuel punp but it did'nt help. if anyone has any ideas of what it is, i would really appreciate it. thanks.

 

Well, it certainly sounds like a fuel delivery issue to me. Maybe you're sucking something up against the intake tube in the gas tank. My first guess would have been a clogged fuel filter or an overheating fuel pump, but since you've already covered those I just don't know. Welcome to the forum, one of the smart guys should be along shortly.

 

Sounds like it's time to flush the tank. I don't think your year has a drain plug, so it may be best to drop the tank and clean it. Make sure the fuel pickup hard line is clear too.

Before you go to all that trouble though, do a fuel flow test. Take the feed line off the carb, the fuel line without the silver bullet inline, stick it in a can and turn the key to on. See if the flow is constant and doesn't drop off. If it stays constant, it's the carb.

 

See? Straight from the keyboard of somebody with more time on their hands than I had tonight. lol. Good advice, so listen to "Mr. T".

 

Your symptoms almost sound like vapor lock.
Do the pressure test and volume test and report back.
Is the fuel tank full? IE all the way to the top?
I ask because there is a possibility that the rubber lines at the fuel tank are old and cracked enough to allow air to be sucked in, causing vapor lock.
An absolutely full tank would minimize the effect.
The suction line from the tank to the pump is the most likely to cause this.
Sometimes the hose will hold pressure but not vacuum.

 

Wecycle, I don't know what you smoking, but it must be some good **** to come up with some of the posts you've written.

Vapor lock does not occur due to a hose leak, it's a heat and/or altitude related issue. Filling the tank, if the lines are leaking, will not solve the problem and has inherent dangers.

 

well thanks for the help i will try out trochoid's thread and then get back to you on how it worked thanks.

 

Clogged cat?

 

Trochoid you are 100% wrong on this one.

 

its teh fuel lines

take your lines off of your gas tank. take carberator cleaner. spray them down, take an aircompresser. Blow them out. or water hose.

mine use to go to 6000rpm if you floored it, then if you tried to hit the gas more. it would bog down untill it died.

its simple fix.

 

Sorry man, but I have to side with T on this one. The old Z cars used to have issues with vapor lock, which they addressed by insulating the fuel lines in the engine bay. The issue is caused by the fuel in the lines getting too hot... However, if there is a hole in the pickup tube in the gas tank, then a full tank of gas should show improvement...

 

Vapor lock is is caused by the liquid fuel changing to a gaseous state (vapor), prior too or in the fuel pump. What you are describing is simply an air leak, which will produce a similiar symptom.

I could be wrong about the 'good stuff' though.

 

I gotta go with this one as well.

 

Could it be in the ignition/charging systems?

 

Nope. If it was an ignition problem, it would be consistant from first start. For charging, if it starts, the battery is up enough for ignition, though, if the alt is dead, the engine will eventually die when the battery goes down. But it would not restart without charging the battery.

 

well i did what trochoid said and turns out the flow stayed constant so tommorow i am taking off the carburater and puting on a different one but another question... would i be able to take off the emissions and still run a stock carburetor or would i have to conect all the emissions again?
and is there anyone selling a weber ida 48 carb and manifold for an 82 rx7 becuase i would like to buy.

 

Who dares to question the legend........there will be consequences.....T is da man

Read up on rats nest removal man, time to do it if its legal in your area.

 

Steve, don't say that. I am neither omnipotent, nor all knowing. Questioning my posts for clarification or errors keeps me on my toes and as a result, I have to think more, which leads to more knowledge.

Often, getting caught with errors or bad info, leads to a more in depth discussion that broadens the knowledge base for all of us. I have no problem getting called on my errors, particularly when it's done in a polite manner as wecycle did.

Sometimes I feel like I'm the info police, correcting erroneous or misleading info and hope that I don't go overboard and **** everyone off. It's all good though. I appreciate the compliments, support and faith that many have shown in my help.

 

I vote for the clogged cat. My 84 subaru did the same thing. It took us 5 hours to drive for Buffalo to Hamilton!

Loosen the joint before the cat, it will be loud, but if she stays running you have a clogged cat.

2 years ago my 85 GS Lost all power and bogged down, cat was clogged. If the air pumps fail on our cars, the cats die very fast.

Adam

 

If the replacement carb has sat for a long time, the fuel has evaporated out of it and left varnish deposits. You may end with similiar, or other problems. If you are sticking with the Nikki, rebuild, or at least clean it out prior to install.

Webers can get pricey, require an aftermarket fuel pump and fpr, along with tuning and poorer fuel mileage. If you can pick one up cheap, and know for sure that it is set up for your engine, that's a viable option. You will need headers and a good free flow exhaust system to reap the full benifits of the Weber.

The rats nest removal makes working on the carb soooo much simpler. If that's the route you wish to go, do it before you remove the carb. Makes carb removal easier.

You didn't mention where you tested fuel flow. If you did it just prior to the carb, then you should be good for a replacement.

 

well i changed the carb and i sprayed out the gas lines but it still does the same thing any ideas???

 

You state that you changed the fuel pump already. What type did you install?

 

Check ignition coils.
I don't know if they would fail completely at one time, or allow a few minutes use repeatedly.

 

Hey, i had a problem simular to this... when i did the RnR, i didnt realize i capped off the bowl vent. To me a couple of days, then one of my older friends (whos a pro. at carbs<i was raised on EFI>) made me feel like a dumbass. He pointed it out, i let it vent over night, never had the same problem again. I still feel pretty stupid lol

 

ok thanks