Coal

I have a 1990 NA and am having some problems with it atm. One of the problems is major fuel consumption, currently I get about 250km to a full tank (not sure what that is in miles). I am 99% sure that there is no leak or anything like that. Also, my car accelerates decently up to about 130km, after that my car struggles to gain any power, I can still hit higher speeds but it takes a long distance to get there. And 5th gear does not generate any power at al really, shift into 5th at 150-160km on the highway and it bogs and does not really accelerate anymore. And when going uphill I lose major power as well. If the hill is steep at all I end up being in 2nd gear, sometimes even 1st. I know most of you are gonna say compression, but if it was low compression wouldn'y my acceleration suck *** as well? And if anyone has any ideas about the massive fuel consumption any info would be great. Thanks.

I only have intake and straight pipe off exhaust manifold with a muffler done to my car.

GLHS

I assume you don't have a cat?

Clogged fuel filter.

Fuel pump is going bad.

Needs a full complete tune up. All fluids, Trans and rear...


Try that, since the car appears fine to you from looking at it and not seeing any blaring problems..

Coal

already did fuel filter and oil, and pretty much new rad fluid. I have only had the car for about 2 months and when I bought it the coolant was almost all gone so I filled it up. It also has not been running for a long time, the people who I bought it off of thought the engine may be blown cause they could not get it to start, but the gas tank was empty, so a bit of ATF and new plugs and some gas and it started. I have the pre cat on there still but after that it is just a straight pipe.

GLHS

keep changing the oil, every 200 miles or less. that will clean out the engine. Make it run better higher up.

Put some TCW-3 2 stroke oil in the gas. 1 ounce per gallon.

Do not drive the car with ATF in the oil..

Maybe the car is still cleaning out the old fuel?

Did you pull the fuel pump from the tank and wipe out the gas tank insides with a lint free cloth?


Have you cleaned the filter on the fuel pump?

Change your fuel filter again, its has sucked up dirt from the dry tank by now..

Coal

I know it is dumping too much gas in, that part is for sure. Anyway to test the pump to see if it is malfunctioning or not?

so far since I have gotten the car I have driven about 2000km, after I burned off the ATF I got the oil changed and then put new plugs in as well. If the precat is causing problems then that will be fixed in about 1 week, header is in the mail and getting precat removed when I get that.

I don't think the filter on the fuel pump is clogged otherwise I would not be using so much gas.

Tell me if I am wrong in anything I say.....

GLHS

I don't understand how you would know your getting to much gas..

Are the plugs fouling out?

Is the car producing alot of black smoke?

Since you said the car is doggy up top, that means to me one of the systems of the car is maxing out. Either its the fuel system, spark delivery, timing, or clogged/ dirty intake system, including the air filter, or clogged exhaust system.


Give me better details on what you have done and what you haven't, in detail...

I may be able to help

Coal

Ok, a couple days ago I put on a new cone filter. The plugs are about 1 month old. I beleive the plug wires are fairly old and need replacing. My friend says that when I first start up my car there is a bit of a gassy smell for a tiny bit that quickly goes away. It also puffs a bit of dark smoke on occasion, mainly during warmup. When the engine is reving below 3000rpm and I am moving, unless in 1st or 2nd gear it is VERY sluggish and weak until it gets above 3000, then it feels normal. When out on the highway it gets very weak above 125km per hour area. as in it takes a good 15 seconds to go from 140-150. No matter what speed I am at, if I shift into 5th gear the acceleration gets much worse, I can put the pedal to the floor and it does not accelerate much at all. I beleive either my alternator or battery sucks real bad as well, when I am stopped and just idling if I turn on headlights, push brake pedal, or turn steering wheel my idle drops and car almost stall, making it hard to keep it idling when driving in the rain at night. The battery is only 2 months old though, leading me to beleive my alternator is not working properly. As I said before from a full tank it only takes about 225-250km until I am just under 1/4 tank left, so I beleive pump is malfunctioning and pumping way to much or something along those lines.

I still have exhaust manifold, header is on the way though. And I have the one pre cat still in there as well. There is also a rattle coming from the Exhaust manifold I beleive, or that general area. After the pre cat it is just a straight pipe to a straight through muffler. Oil was changed about 2000km ago, non synthetic oil put in. There is a brand new fuel filter put in about 1.5 month ago. I have run injector cleaner through, and the stuff that takes water out of gas (cannot remember name of it now). New alternator belt put on around boxing day.

When I bought the car I did the ATF through it once but it was not in there very long. After burning it all off I then got the oil changed and got new plugs in it as well. That was about 2 months ago now.

I will also time it 0-100kmph time and post that and see if anyone thinks it is slow, it feels what I imagined an rx-7 would feel like, but the only ones I have ever ridden in other then mine have had lots of mods done so I cannot compare with them really. I think it is somewhere in the range of 7 seconds area, although I may be way off.

Thanks for the help with this, it is annoying not being able to keep up with cars that I should be smokin on the highway.

GLHS

Your cat is fucked, thats your problem. That rattle is the inside broken up and rolling around inside the piping.


Is causing your car to be slower than normal.


ATF most likely helped ruin the cat. and old age...


Make sure your ports are opened fully, since you won't be able to use them once the cats are all gone anyways.

For now, make sure they open and move fully in their range..

Coal

But that does not explain my excessive fuel consumption from what I understand.....well....maybe it does........I dunno......thanks for your help bud, is much needed. I appreciate it.

GLHS

Your crappy MPG is from trying to make the car get to the speed limit and pushin the pedal down futher is eating up your gas..

I bet you..

Coal

ok, I will post the results of the new header when it arrives, will probably be in about a week. I hope your right with every ounce of hope I've got!