Compression Test Results for my $300 Car
 

Ok, i think i did it right, i did it by myself reaching under the hood and turning the key while holding the gauge, it has a pretty long hose to reach the block. I used a screw driver to hold the throttle open. When you do this, do the other two butterflies open from the vac pressure? or should i find a way to have them open while cranking?

For anyone following these updates... here are previous posts.
If you don't feel like reading my previous posts, i can sum it up. car won't idle, runs bad, stalls out when you give it gas to quickly.

Before i bought the car.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/car-worth-buy-%24300-404731/
And after.
https://www.rx7club.com/2nd-generation-specific-1986-1992-17/%24300-car-update-still-no-go-405564/

I should state that the engine was a little warm when i did it, but not up to operating temp. I got even pulses that stopped at ~50 each time, which a grand total of ~88. I had the same results for both the front and the rear rotors. I should also state i have a lot of carbon built up in there. I pulled my secondary injectors, they were black with carbon, and my 2 day old spark plugs were starting to turn brown and had traces of carbon on them. I know 88 isn't a high number, but i believe it may have to do with the carbon build up.

Today i went and replaced just about all the vac lines i could without removing
the UIM. Still runs bad.

Perhaps you can try the "water-trick" or run sea-foam through the motor. Who knows how well the motor will take it though if it's running that shitty.

Yeah, i read you have to drive it hard after you do the water trick.... i can't drive it hard. So i don't wanna risk it just yet. When i give it throttle under the hood... and it starts to die out, i can spray car cleaner into the intake and it recovers breifly, if that makes any difference.

probably time for a rebuild with a street port

it sounds like a fuel problem first get a spark tester and run it on all 4 plugs try to find the one that looks like a test light its black and clear and you put one end on the plug and put the wire on the other end and start the car it will light up orange and get brighter and dimmer depending on the quality of spark believe me it's a lifesaver it makes it so much easier to diagnose the problem then if your spark is ok then start going through your fuel system filter, pickup screen and all that good shit then if you find nothing if you have a spare battery pull up the cover for your fuel pump and try hot wiring it first with the car off and listen to the sound it makes then start the car and do it again and make sure it sounds strong. Thats what id do. Try that and if it still does the same shit than post again and we'll try a few other things. <BRIAN>

I already used a spark tester, all four lit up the tester, thought i honestly can't recall if they all glowed about the same. I did replace the fuel filter, which was very dirty, i blew black junk out of it. I should make me a fuel pressure tester while i'm at it.

ok now if you have an ohmmeter (works best) or a test light will work ground it then with the car running with the injectors plugged in poke the positive side of the injector plug an see what you get

Well i can only see my secondary injectors, i ohmed them out and they were at 1.0 Ohm which is right on spec. i did that without the harness on. i can't see my primaryinjectors so i can't test them. Or maybe it was a little higher then 1.0, i was reading my manual and it was in spec whatever the number was

I don't think carb cleaner is a good (they usually have warnings on the label 'not for use in diesel or rotary'). I believe it's because it breaks down the oil (not sure though).

ah, ok. well i just did it as an experiment to see if it'd make any difference since i didn't have anything else on hand. like starter fluid.

if you have spare parts then start trying that AFM,ECU,pressure sensor stuff like that try tapping the fuel pressure regulator with a wrench ,try obvious stuff

Yeah, i don't have any spare parts. Do AFM's go bad and you not get error codes? Only error code i get is for the O2 sensor.

at somepoint all electronics go bad just like your computer gets outdated it's not real; common but it does happen and all of those main electric pieces tell your car what to do so if something is screwed up somewhere it could make your whole car run shitty and tell it to do all the wrong things. now youve got me stumped and now i really want to find the problem i'm gonna go look at my car give me a quick rundown of everything it does.BUMP for someone that knows more than me

Quick rundown? Ok first i start the engine, it turns over fine, zooms up to 3000 RPM.... then if i don't do anything it stumbles and dies. If i hold the throttle it's stay running. needs to be around 2000 RPM to stay alive, so i just tightened the throttle bolts to keep it open a little while working under the hood.

If i stab the throttle, it'll stumble and try to die. If i pump it fast it'll respond better and rpms will climb. Before i replaced the fuel filter, it'd have alot of trouble getting past 3500, but now it'll go above that. It's very sensitive about the throttle i apply. i can gently press it harder and sometimes it'll respond, other times it'll try to die. but opening the throttle quickly results in stalling.

I haven't tried driving it again since i bought it like this. it was hard enough getting it up the hill.

Could just be clogged injectors, might want to pull them and get them cleaned up.. those numbers seem kind of low.. but could be to serveral things.. could be low battery or not having throttle open 100%

like trainwreck said it sounds like clogged injectors have them cleaned and let us know or if you want to try some of the stuff you put in your tank get chevron techron it comes in a black bottle and its about 6.00 if that doesn't work than they'll have to be removed and cleaned and if you use the chevron than make sure it's on a quarter tank or less so it's less dilluted the stronger the better or try mystery oil ive unseized a couple of motors that were tight as a drum with that stuff you can pour it right in with your gas the bottle comes in all different sizes get the real small one and pour it in <BRIAN>

hmm i'd imagine the the tips of the primary injectors are coated with carbon, just as my secondaries are covered in carbon. anyway to clean the injectors outside the engine safely? besides sending them off? i'll try that with a spare set of injectors which i can steal from Pull-A-Part.

Sending them off to RC or simlar shop would be your best bet.... but pulling in some injectors from a junk yard is just a gamble.. run a few test on the junkyard injectors before you throw them in.. check restance, Power them up and see if they click, visualy inspect it for gunk and stuff.

hey Ramen

i'm actually in a very similiar situation as u...

i bought a $400 88 TII with similar symptoms...

When i start it, it fires up, then dies without some help

after it's warmed up it'll hold it's idle

u give it gas it wants to fall on it's face and die... if i press BARELY and i mean barely any throttle... i can get it to slowly come up to almost 4,000 rpm then it tumbles and falls on it's face...


I decided to tear off all the emissions bullshit... and simplify the engine, in my quest to resurect it...

i made custom block off plates with gaskets and RTV'd them on...

when I put the car back together now.. it doesn't wanan start.. :(

it sometimes wants to catch ALMOST starts then dies again.. I tried unlfooding it and all that good stuff.. but no luck..

i'm gonna try changing the spark plugs and wires next to see if that helps...

I'm the only RX7 in the whole region... so i don't have spares to swap and test with other PPL... so i'm prety limited

Nobody has told you to check that actual fuel pump. You may not be getting a good volumn of fuel from you rold pump. There is a thread that addresses poor fuel delivery.

Don't do what Ottoman did. Just try to get the car running right.

:p: i told him

How old is the gas?

lol

oops :p

the reason i did it, was to remove the "unneccesary" crap from the car.. all the old and aging crackin vacuume lines and hoses, clogged and crappy Cat... cracking belts... some of the emissions plastic nipples were cracked and broken... all kindsa stuff...

was it really a bad thing ? :(

well, yea. the car won't start now. The smog stuff is not the culprit.

Sorry 88GTU I didn't mean to skip you. I just was glancing at the post

ya but I only found that out AFTER i removed it... if i had said "i removed the emissions stuff now the car works great" then it woulda been a good thing..

oh well.. I'm not trying to drag the thread OT...

i just wanted to say i was having similar issues and would be watching this thread for progress and/or try similar things with my car...