87 t2 when I let it go down the highway it runs great except for slight quick engine cuts around 5000rpm. sometimes happens in fourth. Any help would be greatly appreciated.

Thanks

 

1) Ignition problem - bad spark plugs and/or spark plug wires

2) Possible bad TPS - spec the TPS to make sure it doesn't go over 6k-ohms at full extension




-Ted

 

do you know how much boost you are running? any mods? might be hitting fuel cut.

 

Makes sense, When I bought the car a few months ago it woudn't rev over 5500 Aspec tuning got me out of a bind and put a new tps in it. (I think it was used) I didn't realize the new cut out problem until a few months later. I don't rev out in fifth too often.
no mods yet just trying to get it running perfact.

Thanks alot for help the everyone, Its my first rotary and I like it. Ran a 14.7 @92mph ,170k on it.

 

dam that's fast for a stock car. are you sure it's 100% stock? is it the factory engine? Brand new they only ran a 15.1 or so. and with 170k it would be slower then that.

 

I'm not sure if the engine has been changed . I bought it off a kid who got it cheap with a blown trani, he knew nothing. The car is in great shape original paint never winter driven. I had aspec tune it to factory specs and I put a k&n in box filter in. I ran it all day at the track figured out how to drive it. I was running 15.01 all day. Finaly with a bad reaction time I ran 14.90 so corrected we figure 14.7.

Jim

 

ah ha. that makes a bit of a difference. the reaction time has nothing to do with your 1/4 mile time. you could have a 5 min reaction time and your 1/4 time would still be 14.9 it just means you sat there for 5 mins after the light turned green before you started to move.

still very good for a stock car.

 

Thanks you just settled my argument Ive been having with friends for years. Ok 14.9 with 4 psi of boost. I read its supposed to run 14.4 new.Can you tell I'm new at the rx7 game?

Jim

 

Probably the infamous 3800rpm hesitation. Buy a new ECU.

 

no no, it's over 15 for a stock 87-88. 15.1 I think. and the 89-91 is 14.9 and those are pro driver times with brand new cars. So yours did very well!

 

i have this book (forget the name) its a compilation of A LOT of reviews of the FC (from 86-91). its got a white GTUs on the cover. anyway, as with most 0-60 and 1/4 mile reviews, most magazines get better times 60,000 miles later as opposed to when the car is new. i dunno if this is attributed to break in or just that they get more accustomed to the car. liek for instance they tested an 87 T2 and new they got 15.1 in the 1/4...and 60K later they got 14.8 i think.

also, one review in there pitted an 89T2 against an 89 GTUs. and in the 1/4 mile they got the stock T2 to pull a 14.6! lol...guess they were really good drivers.

but getting back to your problem. yeah maybe either a TPS...or could be the fuel filter. the fuel filter was clogged on my n/a once and caused an upper rpm hesitation when i got on it.

good luck

 

http://home.rmci.net/panther/rx7specs.htm

 

Thanks, thats the site I found the 14.4 et on. I new i wasn't that crazy.

Jim

 

Check for the restrictor pill in the boost sensor line - without it you can get false fuel cut at high rpm/boost. It gets 'lost' quite easily when vacuum lines are changed. Its a little plastic pill that should be installed at the engine end of the boost sensor line - you should be able to feel it by squeezing the hose. The boost sensor is the rectangular black box on the passenger side strut tower btw.

Enjoy the car!

Henrik
87TII

 

I just put a piller mount mixture and boost gauge in and i teed the boost sensor line .I found the line I took off the boost sensor in the tool box. guess what, it never had a pill. Is that the proper name "pill" because I'm gonna order one.

Thanks. Jim

 

umm... just out of interest, how fast are you going at the top of fifth? (mph or kph)

 

the fastest i've ever had the car going is 210km it starts cutting out around 190km . I can feather the gas and get 210kmh out of it, not sure if I could go faster.

Jim

 

Try what HENRIK mentioned. Anytime I take the hose with the orfice off the pressure sensor and put a plain vanilla vac hose with no orifice on , the car will have a large jerking sensation, much like some pulled the plug wire off and jammed it right back on. Put the vac hose with the orifice back on and no problem what so ever. I can duplicate your problem at will just swaping the two vac lines b/t each other. Thing cost maybe three bucks at MAZDA and I've heard that you can buy a similar part at the auto store. The lack of an orifice seems to cause a spike in the reading to the sensor.