RX7Club.com - Mazda RX7 Forum

RX7Club.com - Mazda RX7 Forum (https://www.rx7club.com/)
-   1st Generation Specific (1979-1985) (https://www.rx7club.com/1st-generation-specific-1979-1985-18/)
-   -   Instantaneous Loss of Engine Power (https://www.rx7club.com/1st-generation-specific-1979-1985-18/instantaneous-loss-engine-power-702815/)

morphiend 11-07-07 08:24 PM

Instantaneous Loss of Engine Power
 
So after some preliminary searching, I have been unable to find anything the closely (exactly?) resembles my problem. Hopefully you guys will have some ideas to take a look at besides trying to stab in the dark on this one. I also can't do anything about it at this exact moment since I'm still at work and the car is at home in the garage.

I've got a completely stock 82 (almost all of its the original equipment). On the drive in to work this morning, just got on the highway, and I shifted from 3rd to 4th @ 6K doing 60+ MPH. After about 50-100 feet (and starting to approach my highway cruising speed of 75), all of the sudden there was an instant loss of power. With the accelerator at the same depression, I was losing speed instead of gaining it. I tried revving it to no avail but being able to barely keep it at the current speed. Thinking maybe the tranny went, I dropped the clutch and try to neutral rev it. As soon as I dropped the clutch, the RPMs start quickly dropping and revving would barely keep it at the previous RPM. So I hightail it to the shoulder and pop the hood. I could not see anything quickly out of the ordinary. When the car reached idle, it was running SO ROUGH that the engine was actually shaking quite violently. It would be like an imbalanced engine running. From the feel of it, it's like its only running on one of the rotors, or maybe only half of the rotaries (missing firings). It runs enough that I can start the engine back up, but it runs so rough.

Any ideas? One thing I'm going to check is to make sure the ignitors are properly connected and that my coils are producing properly.

'84-12A-GSL 11-07-07 08:28 PM

Sounds like an ignition issue, check to make sure that all the plugs are firing. Maybe a toasted ignitor.

Rx-7Doctor 11-07-07 11:31 PM

Bad ignitor will not cause those symptons. You can drive around on just the trailing and not have that type of sympton.

You need to check the front and rear plugs and see if one or the other is fouled with fuel or looks like it is getting no fuel.

It could be a compression problem, could be that one side of the primary barrels on the carb is not spraying or that you lost compression in one housing. It still also could be a fuel delivery problem also. Fuel filter clogged or fuel pump failing also.
All of these things have been covered in thread either titled, No power, loss of power, etc...

Recommend you check all things I have listed. I would start with the easy one of fuel volume then the compression test.

BlackWorksInc 11-07-07 11:34 PM

I would say its a compression problem...

I don't know but maybe he blew a seal?

Kentetsu 11-08-07 05:06 AM

Sad to say it, but you've just described the symptoms my car exhibited when I tossed an apex seal on the rear rotor. The violent shaking at idle pretty much nails it. Perform a compression check to find out. Maybe you got lucky and have a different issue, so good luck...

morphiend 11-08-07 09:33 AM

Fuel delivery is not a problem. I replaced the filter about a year ago. I also check the carb last night as well. Plugs should be good as well since I replaced them at the beginning of the year, but I will give them a look tonight since that's a cheaper fix than a seal.

I was originally thinking compression issue, but thought if I blew an apex seal that I would have heard something. Ken, when yours went did you "hear" anything? I read through similar posts and was hoping to hear something like it made some kind of distinctive or any noise.

gsl-se addict 11-08-07 09:43 AM

Nope. I blew a rear apex on my old SA and didn't hear a thing. Sudden decrease in power (I was really low on gas and thought I may have ran out). I coasted into a gas station and filled up. Started okay, ran a bit rough, no smoke, no power. It would only do about 50-55 mph WOT and took a long time to get up to speed. The broken apex took out the other 2 apex seals on mine, so not even one face on the rear rotor was making compression/power.

Did you check spark on the leading plugs? Loss of leading spark can cause a loss of power and rough running. Check spark and then compression. We will then go from there.

bugman1973 11-08-07 10:57 AM

yep same thing happened when i blew up the S3 13b. just running down the interstate to make sure my speedo was working and pop just all the sudden lost power didnt hear a thing just kind of slowed down a bit hard to excelarate

Kentetsu 11-08-07 03:48 PM

While driving, you might not hear anything because it would happen so fast. I was actually idling at a stop light when mine went. Chunk-chunk, putter, putter, putter, etc.

morphiend 11-18-07 03:14 PM

Well it looks like another one bites the dust.

I finally got a chance to perform a compression test on it. Overall on the Front was 70-80psi and rear... 0psi. No I didn't forget a leading digit. I already miss her. ::sniff::

Jeff20B 11-18-07 04:42 PM

Are you near peejay? He probably has some 12A stuff you could get.

85rotarypower 11-18-07 05:06 PM

My 12A went under different circumstances from everyone else. Most people's engines are running at at least idle when they pop, mine popped a rear apex seal when I was cranking the engine. Crank, crank, crank, BANG, sputter, die. It was a unique experience, not something I would want to live through again.

yetterben 11-18-07 05:48 PM

shitty i have lost two 1st gens this way once around a corner and another at hwy speeds. Also my beloved 88 t2 :( I belive the 88 was cause of the fram filter i put on it for oil. tough lesson but lesson learned none the less


All times are GMT -5. The time now is 10:02 AM.


© 2024 MH Sub I, LLC dba Internet Brands