Hi all, still a noob to this site and still learning lots about my fd.

92 rx7 - engine is bone stock other than bov and exhaust.

Problem - When i accelerate i'm not getting any boost and around 3000 rpm it chugs violently. Kinda like if you were to almost stall a vehicle starting in first gear... Anyway as long as i keep my foot down it gets through the chug and then the turbos kick in like a freight train. it's only around that 3000 rpm range and lower. Now i just bought this car so i don't know it's history too well but the previous owner said that the headers need to be replaced. He gave me a brand new set with gaskets and all. can an exhaust leak actually be the cause of this? By the way it does this in every gear. and as long as i don't drop below certain rpm i'm fine....

Thanks for any help provided!

 

If you do a search for 3000 rpm hesitation you'll find this is a very common issue with several fixes, varying from soldering to buying a Power FC.

Also, if the previous owner thought the FD has headers and also did work on the car himself, you may want to start doing a very thorough check of the vehicle...

 

even with teh small kick you feel when the second turbo kicks in your car should not chug or any of that even if the turbos weren't working .


what are you boosting ? at 3k rpms ? do you have a boost gauge?

and if the PO changed the headers on the car I dont think he has a very detailed history of either. he probably ment to say down pipe

does the car have a FULLL exhaust? or just downpipe , and muffler ,

if your car does not have a CAT , and is still on stock ECU then you have a problem .

 

+1 if it's a full exhaust it could be fuel cut from over boost.

 

Unfortunately no boost gauge yet
i have full exhaust with a cat

Upon further inspection and test drives it seems that my primary turbo isn't coming online at all. from 1800 rpm till 3000 i get no boost, after 3000 it chugs and jerks like i'm about to stall it and then around when the secondary normally comes online i get boost.... However when the car is at operating temps for a while the chug and jerk is less noticeable but still no boost until about 4500 rpm. The previous owner did do a motor swap. it was professionally done but i'm thinking during the install the may have knocked something =(

Also when i accelerate even the slightest bit, as long as i press the gas pedal i hear a bit of a ticking noise or something... needless to say i'm getting a bit worried now. I've tried to listen for any sort of exhaust leak but can't hear much of anything.

 

a boost gauge and wideband O2 gauge would be wise purchases before doing much else.

I had a very rough acceleration issue when boosting, when I installed my wideband, it turned out that my car was having very lean spikes and probably would have blown up had I not simply immediately installed a PowerFC after that.

 

That particular bit would make me want to adjust the TPS (Throttle Position Sensor).

My FD had the issue to varying degrees for quite some time. It did it when it was twin turbo, and it continued after going single turbo.

Adjusting the TPS fixed it entirely.

Now I can do 20mph in 3rd gear and accelerate, which was pretty much impossible prior to adjusting the TPS.

Do a search, there are a number of threads on this, and you should be able to find some good instructions on it.

I've attached the doc I have on it, this may be from Dale Clark, I can't recall. These instructions work if you have an Apexi PFC.

The standard instructions are in the Service Manual.