Sir Rupert Hobo

well, here are the symptoms.

1. gas milage. around 8 MPG. if i stare long enough i think i can actually see it move.

2. i CAN'T get my idle down to 750. i tried to adjust it with a multimeter, but can't get 1000OHMs...

3. i'm running very rich.

4. my idle won't stay still when my motor is cold. it bounces from 1100-1400 until warm, then settles at 1100. no vacumm leaks.

5. about the "knocking". this only happens in 4th and 5th gear. at 3000rmps and up and i don't have that much power. it might happen in the lower gears too, but i can't really hear it.

so i called a local rotary shop. the guy said it could be that the side of the rotor is hitting the housing etc. and not the seals. could that be it, maybe?
_________________________________________

i had JUST done a complete tuneup. cleaned my injectors(by cruizin perf.), new plugs, fuel filter, air filter, oil change and filter, flushed coolant, and checked that my fuel pump is flowing good etc. the motor was rebuilt 15,000 miles ago. with TII housings and streetported. i'm running with no ACV/airpump but i have a cat that was replaced 6 months ago. and a new O2 sensor.

so what do you think i should check for? i tested my coils. i used my multimeter and i got no reading... it should be between .2-1.0 OHMs right? am i doing this correctly? i'm following the haynes manual.

i'm lost.

Rx7Ridah

iTrader: (8)

what octane gas? heat range plugs and leading and trailing plugs in there respective places? and lastly is ignition timing set properly? sometimes its the dumbest thing thats overlooked.

Rotary Racer

I will have to let this one brew in my head for a min or two. But the first thing that pop's out at me is your running no smog equipment, BUT you still have a cat in there. This could be one of your problems (possibly melted the poor thing to death). Some of the symptoms you mentioned:

A. has no power
B. bad gas mileage

Most of those point to a clogged exhaust system. Might want to think about getting a race pipe and get rid of that cat.

- Dana

Sir Rupert Hobo

87 always.
plugs are in the correct order.

i'm not sure about the timing. i tried and i still don't understand how to correctly tell if it's right or not. i've searched but i just don't quite understand the info that came from it.... what would set the timing off anyways?

pyrojunkie

A cat is pretty useless without the airpump. The converter needs oxygen to work.

Sir Rupert Hobo

Dana, i've thought about that. and am seriously thinking about gutting my cat.(i GOTTA atleast have that "visual" effect incase the cops have a look-see)

Rx7Ridah

iTrader: (8)

well to check the timing a timing light is needed. here is the procedure as per factory service manual. 1. Run to normal operation temp. 2. turn all electrical loads off (i.e. heater fan, radio, etc) 3. Connect a tach (or use an assistant) 4. Check idle speed. 5. connect timing light to L-1 plug wire. 6. point light at ecc shaft pulley should light up yellow mark on pulley or first mark if your paint is worn off. repeat for T-1 plug wire only should light up on red mark or the second notch in pulley if paint is gone. If out of time loosen the bolt that holds the crank angle sensor in place and turn the cas until in range. you may have to readjust the idle speed using that little screw on top the throttle body to compensate for idle speed. hope that helps

Sir Rupert Hobo

thanks for the info. but a couple questions.

my pulley has 4 white marks on it. no yellow. i'm assuming i should line up with the one farthest to the right?

also, if my idle speed is off, then i won't be able to correct the timing because it is not set properly. i have to get my idle down in order to get my timing right.. is this true?

Russ

your cat is bad, either gut it or get rid of it.

1SxyRXy

did you say you also cant adjust your TPS right? maybe they are bad?

pip

87 octane sucks imo =/ My car likes to stall if I run anything lower than 90. Also your idle problem sounds like a bad tps if you just CANT make it to 1000ohms

Sir Rupert Hobo

ok, here's what i'll do.

get a used TPS and gut my cat/wire my ports. also i'll have to check my timing..

i'll update this thread once it's all done.(i don't have another day off till friday)

but please keep the suggestions coming.

F1blueRx7

iTrader: (5)

Just because your engine is a low mileage rebuild doesn't rule out the fact that it might be blown. All the symptoms are low compression symptoms. When I have these problems I ALWAYS check compression prior to troubleshooting. Second to that, timing, TPS etc.

Sir Rupert Hobo

update.

well, i gutted my cat and wired my ports open today. it seems to get WAY better gas milage. but less power down low(because of the ports)

on the other hand, i still have that "knocking" noise. it COULD be a blown motor, BUT i really don't think it is. i'll do a comp. when i have the time. and i got to thinkin, could it be my rear end? my tranny? could i be losing power because gears are "slipping"? i'm not really sure where the hell the noise is coming from cause the motor is to loud.(n/a with headers... of course it'll be loud )

remember, this only happens in 3,4, and 5th gear... but it might be doing this in 1st and 2nd as well(again, too loud to tell)... i forgot to say in my first post that, there is no knocking noise it neutral...(sorry i didn't mention that earlier.)

any whoo, my idle is bouncing up and down ALL the time now.... not just when my motor is cold. i'm waiting for a good/used TPS. i should be getting it mid next week.

Molotovman

iTrader: (49)

Do you have the right thermostat?

Sir Rupert Hobo

i've thought about it, but what would that have to do with this? just wondering.

but, thanks for the tip. i'm getting one in a few days.

tong53

yeah 87 octane is bad for a turbo...but we lucky na guys get to use 87

Molotovman

iTrader: (49)

wrong t-stat opens and closer weirdly causing the coolant thermosensor to send wierd information to the ECu causing the car to run weirdly. Replacing my T-stat fixed my bad idle and crappy running engine.

Sir Rupert Hobo

ahh, i see. i'll try and get one tomorrow.

Raymr

Theres a small screw with a locknut on the front of the throttle that holds the plates open a little. Try backing that out a bit.

Also if your rebuild has a pulley of hub from a different engine, there is no guarantee that your timing marks will be correct, since they are machined in matching sets. There are other threads that talk about repunching the timing mark on the pulley.

SOIA

Your knocking problem is most likely your transmission, your countershaft bearings are probably worn out, 1,2+3 gears are on the mainshaft and 4+5 are on the countershaft. Hope that helps, perhaps a thicker gear oil will help until you can fix it.

Wankel7

Have you checked your fuel pressure during a full throttle run?
https://www.rx7club.com/showthread.p...=fuel+pressure

James

Sir Rupert Hobo

great link James.

if it's the tranny, that's a good thing. i've got 2 TII spare trannies in my garage

i also bought a new thermostat... but it's raining

Sir Rupert Hobo

one more thing. i'm hoping it dries up tomorrow. if it does, i will be putting in my thermo. and ground everything.

i got a question... is there a limit to the thickness of the wire? could i use 4-8 gauge wire instead of 10?

Wankel7

Considering that for 100 feet with 10 gauge wire you lose about .8 volts I think 10 gauge would be more than fine.

http://www.securityideas.com/securit...tocalvold.html

James