c00lduke

Ok I have finally decided to figure out why my car preformance is comparably to a Geo Metro. About a month ago my mom flooded the engine and i couldn't get it to start, even with taking the spark plugs out and turning it over a few times. So i took it to a preformance car shop in the area(it was either that or the dealership) and they told me something about the seals. The guy spoke awful english and i couldn't really understand what exaclty he said. But my dad wanted a 2nd opinion so we took it to the dealership. They fixed it and he said he did exaclty what i did to make it run again. But he said it has low compression like 5.3. Thats all i know about what he said nothing about if it was front, rear, or whatever. So i've been drving it with "low compresion" using that as my excuss for why it is so slow. But recently someone told me that low compression shouldn't make it slow. So what else could it be?

Number 2:
My boost pattern is like this: 1st gear anywhere from 5 vac to 3 lbs boost
2nd gear 5 vac to sometimes no boost at all
3rd up to 11 and just keeps dropping
4th regular boost pattern
5th to wet to find out
If i ever get 7rpms boost is at 0-1

Someone told me i could have clogged cats, how would i figure this out?

Pretty much i can feel the pull and so can everyone else that is next to me but the car next to me but keeps going by with out a proablem. can beat all cars up to 30mph but after that i have no chance.

So any tips on what it can be would be great

~Luke

suganuma

thats REALLY low compression.....
is it really hard to start and doesnt want to hold an idle??

what mods do you have??

if you havent already get rid of the precat and put in a downpipe.

give us more info on the car.....miles, maintanence, etc

technonovice

You could have MULTIPLE problems. If your compression is low that would explain the starting difficulty and some power loss. Clogged cats (both) can cause boost issues and obviously rob power.

If you rebuild replace the precat with a downpipe, the cat with a Bonez unit and get the silicon/tie wrap hose job while you are at it.

Coulthard Fan

Do this first - your boost pattern is fucked. Once you have your boost right you can worry about the compression - I bet the dealer screwed up the measurement anyway.

Scott

technonovice

http://home.iSTAR.ca/~dvandit/TurboT...shooting.shtml

Idle should be about 16 - 18 in Hg.

You need to do the 3rd gear test. Go steady 35mph then floor it.

At WOT, 3d gear, everything stock, boost cycle is (rpm's approximate):

rpm psi
3,000 10
4,500 8 (as 2d turbo comes on)
4,500+ 10 (recovers almost immediately)
6,000+ 8 (and holds to redline)

mightyslash

I don't think so. He might blow the engine if he runs full boost, considering his car's condition.

technonovice

Good point. I'd get a second compression test from a recommended shop.

mightyslash

That's what's happening to my car right now. It ain't running full boost because there's vacuum leaks and boost hose leaks with the precat still on. But the good thing is that the low boost keeps the engine running. I can't run it hard, it's not able to do so. The bad thing is that my car gets slower.

Coulthard Fan

Blow the engine from running normal boost levels with "low" compression? Why do you think so? If they say his compression is 5.3 or thereabouts on all 6 faces I bet they screwed the pooch when they were measuring it. If he truly has low compression on one or 2+ rotor faces I'd agree with you wholeheartedly. Either way, I think he should take it to someone who KNOWS how to do the vacuum lines and get his boost straightened out. While they have it apart - and before installing the new silicone lines - they can retest the compression if that makes him feel better.

Plenty of people have run motors for a long time with below average compression... and I don't think that had much to do with a subsequent engine failure. Most folks just overheat=O rings or detonate/run lean=apex seals.

That said, I'm not a mechanic, but I've been around awhile.

Dustin

I wouldn't classify myself as a know-it-all, sarcastic bas$#!d, yes. In anycase, I would bet you probably have a RX-7 that suffers from several problems. When I bought mine, it ran like poop as well. After weeks of reading this forum (BEST SITE IN THE WORLD) I decided that the best way to fix the car was to simply do all of the maintenance the guys on the forum recomend you do when you buy the cay. I did a tie wrap job, downpipe, gauges, plugs, wires, and for fun put in a mid-pipe(shouldn't have done the last one b/c now I run too much boost). In anycase, where before I couldn't beat an integra off the line - now the beast breaks loose if I don't watch it.

So, the moral of the story is - do the reliability mods (vacuum lines, downpipe, gauges, plugs, wires, etc) and I bet you run like a million.

Dustin

c00lduke

Thanx for all your posts guys, to answer a few questions:
it has 93k miles, been taken very well car of, drivin hard (nothing to unusual), and no mods (yet). It doesn't have any problems starting and i always let it warm up, being that it is 15 here in kansas. Also, it is a beast of the line up to 30mph then "bogs" down after that but when i do a 4th to 3rd drop i have so much power then it "bogs" down again.

hope that helped

~Luke

legendr35

the bogging you feel is most likely caused by fuel cut.

c00lduke

And someone was also worried about me blowing my egine if i ran it to hard. There is no fear on my behalf i still run it as hard as i can when the time is needed.

~LUke

Red-Rx7

Luke-

Glad to see you make it over. We will take a peek at it when you bring it buy next week... There could be quite a few things wrong, but we should come up with something.

Mike

c00lduke

No problem Mike, but sometimes my brower automatically goes there and i don't even realize it untill i see Jameson's avitar. I can't believe they made the exact samething just with a 'S'. Yeah but hopefully we can figure out what going on with my car. I checked through the records and the fuel filter was replaced twice in 98 with 60k miles now it has 92k, but I can't seem to find anywhere how ofter you change it. But just give me a call when the pillar is in and when a good time is for you to give me a little help with my car (if you can).

Thanks

~Luke

technonovice

It is time to replace it. The FSM says every 60,000 miles but 20-30K is about it in reality. It is a PITA.

Just in case here is a How to:
http://www.rotarypowered.com/howtofuelfilter.html

rotarhead

sounds like you need a downpipe if you were suffering from fuel cut you would have some severe power loss i would not attempt installing downpipe yourself cause with a 93 with those miles you will most likely break a stud. take it to a good
shop (dealership won't do it cause your taking of a cat) replace the precat with a downpipe and see what happens. if that doesnt work you should go the vacuum line route. again i would get a service technician to handle that one as well unless your very patient person or you will run into trouble. good luck sorting it out.