stv

Hey Fellas,

some friends and i went out for a drive tonight out to the local dam. once we got out of town we were cruising pretty hard. It has a super long straight on it, but there was a outer towner dad cruising along under the recommended speed, my mate was like drop it to second and boot it so i did cos i hadnt done that before. so I over took the car, dropped it back to second and yeah then up to third and away we went.

Now here is the problem once we got up onto the dam. My car went from running where it runs at 900rpm on idle super smooth and tough sounding, to around 350rpm real slow barrp space barrrp instead of smooth barrrrrrrrp. The car is producing no smoke or anything of that nature. No overheating, infact its under the half way mark on the temp guage(s5 rx7). No leaks of oil or coolant. Then on the way home when i went to put my foot down it seemed like it was struggling and boosting seemed to take longer.

Now i know my water pump is on the way out, could it be possibley that? Or could i have popped of a vacum line, or should i think more worser things.

The car is a 1989 turbo 4inch exhaust, pod filter the ac pump is unhooked. umm what else nothing engine wise its all pretty stock. Please guys if you need more information on anything let me know. Also the temp here is oz at the moment is really cold.

I just want to know have i just blown a hose off or am i looking at something super serious tomorrow and i should be ready for it.

Thank you,
Steve


PS. with my previous diff problem there was no problem it was just a freakin heavy going mech diff that doesnt like to be babied around corners.

hIGGI

iTrader: (7)

sounds like u boosted hard and some of the vacuum hoses did not stayed at place and now u have vacuum leak

MattB

did you say 4 inch exhaust...??? isnt that a little overboard?

hIGGI

iTrader: (7)

maybe its just lenght?

stv

heh well its bigger then 3 i know that much, and it was on the car before i bought it. it all was. i havent really had it that long, ii think it got here start of june from japan. anyways yeah back to the problem and ideas please

hIGGI

iTrader: (7)

search for vacuum leaks first

ultradef

How much boost are you running? Any fuel mods?

stv

no fuel mods, and stock boost

stv

bumpy dumpy

one guy today said an apex seal could be gone, but wouldnt i at least notice that happening :| or some signs of it occuring or can it just come like a theif in the night and you not even tell, till you stop.

Mura

I have a question, first how fast were you going before you dropped it into 2nd?
2. Why did you drop it into 2nd and not in 4th? Wouldn't it have been a wiser choice to drop it into 4th and not 2nd?

stv

i was doing around 70km/hour.

Rx7Ridah

iTrader: (8)

do the "compression test for dummies", pull the leading plugs, pull your egi fuse and unplug you crank angle sensor, then have someone try the start the car with the gas pedal on the floor while you put your finger in front of the spark plug holes. you should feel and hear a nice solid psht psht psht, about .5 sec apart or so but nice and consistant on both rotors, if you get psht.....psht psht, then you my friend have lost an apex seal. but if you are only running stock boost with no mods it should be pretty hard to do, however you said it has an oversided exhaust system, and in most cases that will cause an increase in boost pressure over stock, so if you only have the stock boost gauge and the exhaust was already on the car when you purchased it, chances are it could have a fuel cut defender on it and be running more than stock boost without you knowing so. but if your finger compression test (which is only a ball park and easy way to check for bad seals) comes out okay, then you either blew off a vacuum line somewhere or check the inlet tube between the mass air flow sensor and the turbo for cracks, its very prone and will mess idle and such. good luck.

RXgirl7

you should be ideling at 750rpm, not 900...

RexRyder

iTrader: (10)

Most ppl's car shakes at 750 vs 900 (mine does). Anyway, check your plugs/wires.

stv

me and my friend did the poor man compression check, which resulted in no answers, as both rotors sounded fine. which is a good thing gonna do a proper check with a piston engine checker tomorrow. the plugs were fouled so we cleaned them and havent been able to check the spark leads, again have to do that tomorrow. could i have somehow blocked my injectors?

thanks for the help so far.

dsmrx7

Check your injector clips, maybe one came loose. (Happened to me once, I thought I lost a seal during one of my "spirited drives.")

jono20

the same thing happens to me when I run my car really hard, I think its due to overheating. dont trust the stock temp gauge for much..

Mura

If you should be idling at 750 in Drive, then I'm doing good. If you mean that you should be idling at 750 in Park......please come down to Orlando and tell that to Ortiz Racing.

stv

thanks for the replies ill definately check the clip tomorrow.

stv

well i ended up doing a proper compression check, and well the 3 bounces werent even on the rear rotor. so it looks like i will be tearing down the engine to replace them apex seals. *sigh*

Sideways7

iTrader: (7)

How uneven were they? Also, was there one strong and two weak, or one weak and two strong. One strong and two weak is a bad apex seal, the other is a bad coolant seal. Also, its only a huge diff in compression that is bad. Post your approz numbers here and we can point you in the right direction. Was there a pop or somthing that could indicate a ping that would break the seal?
Also, did you ever test for vac leaks?

stv

nope i didnt test for vac leaks,

and it was one strong two weak.

the front rotor is making around 110psi where as the rear around 80 but if you hold the reset button in on the piston checker, the front rotor has even bounces as it cranks, while the rear has one strong two weak as it cranks.

stv

i just need a answer before i pull out my engine does what i described deffinately mean its a apex seal, or could i still not be firing spark or something else.

please, as i really dont want to pull it out and tear it down to find it wasnt the problem at all.

thanks.

WonkoTheSane

iTrader: (2)

One strong, two weak indicate apex seal failure. That's it. Sorry

Sounds like it's time to build this engine up

stv

thanks and roger off to fix i must go.