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-   -   88 rx7 loses power when accelerating (https://www.rx7club.com/new-member-rx-7-technical-256/88-rx7-loses-power-when-accelerating-930347/)

sidewayz88Rx7 11-11-10 11:43 AM

88 rx7 loses power when accelerating
 
I just bought my first 88 rx7 about 2 weeks ago, all i have done to it is, change the fuel pump strainer, and get the oil changed, but when its idling i will rev up with a little hesitation, but when i put it in gear and try to drive it bogs down unless i barely hit the gas and gradually build up speed, idk whats wrong, im probaly gonna change the plugs and fuel filter, but idk if anyone has had this problem and knows how to fix it

thanks in advance

RotaryRocket88 11-11-10 03:13 PM

Have you compression tested the engine yet? I'd rule out a blown engine trying to track down a potential fuel delivery or timing problem.

o5rx8mazda 11-11-10 06:21 PM

mine does similar thing but itll drive fine once i restart it.. CEl comes on and i cant go past 3500 rpms until i shut it off and turn it back on.

sidewayz88Rx7 11-11-10 09:17 PM

i changed the plugs today, didnt help, im gonna change the fuel filter tommorow, and get it compression tested, to see if i can find anything out

RotaryRocket88 11-12-10 10:52 AM

I'd try things in this order:

1) Compression test
2) Check timing with a timing light
3) Inspect AFM plug and test AFM resistance values
4) Check fuel pressure


Originally Posted by o5rx8mazda (Post 10315423)
mine does similar thing but itll drive fine once i restart it.. CEl comes on and i cant go past 3500 rpms until i shut it off and turn it back on.

That's called limp mode, which is an S5 only thing. Your metering oil pump (MOP) is electric, and likely having a problem. When the pump fails, the ECU puts the car into limp mode to prevent engine damage. A side effect of this is the ECU usually has a section burn up at the same time.

Check the engine code to see if it is in fact the MOP: http://www.johnr.com/cpucodes.html.

sidewayz88Rx7 11-13-10 11:15 AM

i still havent figured it out, i brought it to a guy yesterday, and he told me the oil metering pump thing, b/c i have a 91 engine, and my ecu wasnt giving us any codes, so i went and got a ecu, and now its not even starting, so idk whats wrong, gonna be a long weekend, gotta get it running by monday

RotaryRocket88 11-14-10 12:26 AM

Put the original ECU back, and follow the code checking procedure more carefully. If you unplug the ECU or disconnect the battery, all codes will be lost until the problem re-occurs. What you described is definitely limp mode, so you need to confirm. If/when you confirm the pump has stopped working, you'll need a new ECU anyway.

sidewayz88Rx7 11-14-10 12:50 PM

ok i got the ecu to give me an error code, it gave me 26 which is the MOP according to that link you sent me, how do i fix it, is there a way to override it and just put oil in the gas everytime, what is the easiest/cheapest way to fix it

RotaryRocket88 11-14-10 07:52 PM

There is only one way to bypass the MOP and avoid limp mode (without going with a full standalone EMS). You can chip the ECU through Pocketlogger, and remove the code for limp mode: http://www.pocketlogger.com/index.ph...age=1&ecu=S5NA. You'll then need to premix the gas.

Otherwise, you'll need to find a new, working MOP. And you'll need to hope the extra ECU you bought was not damaged when you put it in the car with a non-functional MOP. As I mentioned before, a failed MOP can burn out part of the ECU.

silver80sa22c 04-01-13 04:50 PM

88 t2 with s5block and trans
 
Hey guys I have the same problem I think.ill start my car up and it will drive great for about 5 mins then it drives crappy and has no balls and I shut it off and turn it back on it is fine for a few minutes then back to normal. Any ideas

BLKTOPTRVL 04-01-13 04:57 PM

Check the cats, they might be clogged.

Gumd02000 04-01-13 10:42 PM

you might put a guage on your fuel pressure and keep on eye on it while doind a load test

AquaJ 04-05-13 04:28 AM

Is there any unstable manner/choking/gas smell when trying to rev up after the engine is properly warmed up which don't present when at low rpm/idling?
if so, it's mostly possible to be an inaccurate ignition timing.

satch 04-05-13 08:52 AM


Originally Posted by silver80sa22c (Post 11425444)
Hey guys I have the same problem I think.ill start my car up and it will drive great for about 5 mins then it drives crappy and has no balls and I shut it off and turn it back on it is fine for a few minutes then back to normal. Any ideas

And check the Water Thermosensor as well if the exhaust checks out okay.

misterstyx69 04-05-13 09:13 AM


Originally Posted by sidewayz88Rx7 (Post 10317781)
i still havent figured it out, i brought it to a guy yesterday, and he told me the oil metering pump thing, b/c i have a 91 engine, and my ecu wasnt giving us any codes, so i went and got a ecu, and now its not even starting, so idk whats wrong, gonna be a long weekend, gotta get it running by monday

Nothing ever gets fixed right when you "need it Right away"!
...
Now,you mentioned a 91 engine in an 88.
Is the engine running as an 88?..or is the Harness FOR the Engine?..Did the Swap entail wiring alterations?..

SURB?S 86 RX-7 04-25-13 10:19 PM

Noticed a loss of power after 4k rpm's and also would not go over 95 mph. I pulled of the catalytic converter and the pre cat was all in pieces in the mid cat. Gutted all 3 cats and no more problem.

Nathanieltahoe 01-19-18 01:28 AM

Question about your fix?
 
Idk if you ever got it fixed but I recently purchased an 88 RX7 GXL that sat for 15 Year’s replaced fuel pump/ strainer and batter started up. She will slowly rev up but not quickly or it will be struggling to get up there if not at all. If I put her in drive/ reverse it dies instantly, New spark plugs, what was your fix?

Originally Posted by sidewayz88Rx7 (Post 10314760)
I just bought my first 88 rx7 about 2 weeks ago, all i have done to it is, change the fuel pump strainer, and get the oil changed, but when its idling i will rev up with a little hesitation, but when i put it in gear and try to drive it bogs down unless i barely hit the gas and gradually build up speed, idk whats wrong, im probaly gonna change the plugs and fuel filter, but idk if anyone has had this problem and knows how to fix it
thanks in advance



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