79seven

got in my 88 vert to go back to philly, and have no power at all. I drove her from philly to upstate PA yesterday, parked her in my parents garage overnight, came out today to go back home and I have no power must get to work tonight. I changed plugs, car will start, idle horribly and barely move, what can I do I usually do the search, thats what im doing now but i thought I'd post real quick , for some quick help.

Thanks

79seven

jsut to update, checked exhaust its not clogged, fuel pump is working, what else?

SonicRaT

iTrader: (6)

Check compression.

dynevahn

Hey man check compression, I just went through the same thing. My back rotor had no compression. I hope it isnt compression, check that and get back reply back.

79seven

how can I check compression if engine wont hold idle, I never did a compression check before. My add coolant light did come on right before i pulled away thats when i shut it off and added coolant, then proceeded to drive and no power. I havent had any white smoke, so im just guessing that its not internal. BUt if yall can walk me through a comp check, i'll try that.

79seven

also to add that when my 90 gxl lost compression in her rear rotor, I also had a lot of backfiring and pops in the exhaust, and the symptons are almost the same now, no power, not holding idle, except there are no pops in the exhaust this time.

allforjesus06

Taken from http://www.rotaryresurrection.com/comp.html

Poor Man’s Compression test(free):
1. remove lower sparkplug and wire from front rotor.
2. remove EGI fuse from underhood fusebox to prevent fuel and spark while testing.
3. have an assistant crank the car over for you, while you listen under the hood at the compression pulses coming from this plug hole. IT is recommended to put your hand/finger right in front of the hole to feel the pulses of air.
4. There should be one strong pulse/whoosh of air per full rotation of the crank pulley. Use the timing marks on it as a reference. There should be 3 even pulses in succession, without skips or gallops.
5. IF one or more pulses are weaker or non existant, this indicates (usually) at least one blown apex seal and severe internal damage. A full rebuild will be required, and no further troubleshooting will help.
6. IF this chamber passes the compression test, replace this plug and repeat for the rear. The rear rotor blows more often then the front on 88 and prior engines, and the front rotor blows more often on 89 and later engines, for reasons unknown.
7. With both lower plugs out at one time, you can listen/feel for compression on both rotors at once. This should be a rhythmic ch-ch-ch-ch-ch-ch sound, like an old steam engine train, alternating front to back, once per rotor per rotation. Any skips or galloping indicate loss of compression.
8. note that this procedure can be used to test junkyard engines or engines out of the car. You will need a 19mm socket and ratchet to turn the front crank pulley bolt clockwise in quick, long strokes as possible to get a somewhat accurate reading. You will obviously not be able to turn the engine much at a time, so try to count each pulse as you go.


Compression test using a piston engine tester:
1. note battery strength. A weak battery will yield low compression results.
2. Remove both lower plugs and wires.
3. remove EGI fuse from engine fusebox.
4. have a friend floor the accelerator pedal, opening the throttle for more airflow
5. insert your tester into the leading hole
6. hold the valve on the side of the tester open
7. have your friend crank the car over for 5+ seconds.
8. observe the needle bounces. You should see 3 in succession without skips, even bounces, in roughly the 30-35psi range.
9. let out on the valve now, and let the tester reach an overall compression value for all 3 faces(highest of 3 will be displayed). 115+ is like new, 100-115 is healthy, 90-100 is getting weak(1 year or less in most cases) below 90 could blow at any moment.
10. repeat for opposite rotor. Note difference in overall compression between rotors, which should be no more than 20psi max.

79seven

thanks a lot ill try

79seven

ok now. I did the poor mans comp test and the front rotor has strong pulses all consistant, and the rear rotor has weak pulses, all consistant. So what is the diagnostic for that, also what cause that she only has 118,500 miles, I only had her for 6 months, and I did all proper maintence, I was premixing also, what neglect did the previous owner do to my Kimmy.

allforjesus06

age/poor maintenance. usually the rear rotor goes weak before the first.

since you premix, i got a suggestion. remove your EGI fuse- it's under your hood on the driver's side in the little fuse panel, remove your spark plugs, and then pour some 2 stroke oil in the leading(bottom) holes. sorta "tap" the key to slowly turn it over some, and then put everything back together and then try to start her.

i've heard that too much fuel in the combustion chamber can mean low compression, due to the seals and all not being lubricated properly.

WAYNE88N/A

regular motor oil works better- also you won't need to "tap" the starter...if you must turn it over, do it with the belts or a 19mm (3/4") socket, but I never had to turn the engine once I injected the oil ('bout 10-20 cc's worth through the leading plug hole)...you should be able to get her started even though it sounds like your rear rotor/ seals are getting worn (or stuck)...Remember, even though you're premixing now, all the gunked-up carbon from its "previous life" is still in there...