Net Seven

iTrader: (5)

Yesterday night I was driving my car from my friends house and I decided to take it upto 7k. It started going then started bucking like crazy once it hit 4k.

Now today I was told to put MMO into my gas and fill up which I did. Same thing, except now it doesnt really buck, but once i hit 4k it like stops at that and rpms climb really slowly. I dont think MMO stoped it from bucking, because it wasnt doing it as much that day at all as yesterday night.

I also noticed that when im taking up past 4k slowly and not at WOT its fine. Once I WOT it, the car loses like all the power and hesistates paste 4k rpms.

I changed the boost sensor and its still the same... please help me!

autocrash

holy ****... and you claim you've searched? and did you bother to READ ANY OF YOUR SEARCH RESULTS????

This is like the second most talked about thing on this board some months...

There are like 30 potential answers to this question, make a list and start checking...

vaughnc

Net Seven,

Hey don't mind autocrash. The right search term is "3800 hesitation."

Basically for whatever reason (electric, fuel delivery, etc..) your 2nd set of injectors aren't flowing fuel properly. They kick on at 3800 rpms, and that's where the stumbling happens. It usually has to do with dirty fuel injectors, bad grouding on the injectors, etc.. etc..

A few posts to look through. Of course searchin for 3800 hesitation will yield even more posts. There a good writeup in the "2nd gen archive" section too.

https://www.rx7club.com/forum/showth...hreadid=109251
https://www.rx7club.com/forum/showth...hreadid=116782
https://www.rx7club.com/forum/showth...hreadid=114323
https://www.rx7club.com/forum/showth...hreadid=103145
https://www.rx7club.com/forum/showth...hreadid=116482
https://www.rx7club.com/forum/showth...threadid=99686

Let us know if you need more help after reading up

autocrash

lol... no **** "don't mind autocrash" ....something tells me I was having a bad night last night... lol.... sorry man, shouldn't have been so rude....



...my head was other places....

Net Seven

iTrader: (5)

All this started hapending after i put HEET water remover and some fuel injection cleaner in and got gas at 76. I drove it and sometimes it would start really crappy, like I would have to give it gas to keep it running. It would start up and almost die, then after i give it some gas and keep it at 2k for a little bit like 20 seconds it runs fine. Then when I was at 1/2 tank I got cheap *** arco gas to full tank. Next night is when problems started happending with hesitation.

To me that sounds like maybe its my injectors. What do you guys think? What would be an easy way to fix this? If it comes down to getting them cleaned at a shop, how much will they charge usually?

Thanks for the responses.

Aaron Cake

iTrader: (1)

If you put all that crap in your gas tank, it sounds like your injectors are clogged. Have them professionally cleaned. Most diesal shops will do this for a small fee if you bring them the injectors...

When will people learn: ONLY GAS (and injector cleaner or premix) goes into the GAS tank.

autocrash

Hmm.. this is starting to sound a lot like the problems experienced by StarionX. Does it idle poorly only when the engine is warm?
In the manual, they reccomend checking the battery ground...
So StarionX and I will be installing grounds to basically everything next week, I'll let you know how it goes.

(btw, StarionX has basically brand new injectors in his car... so those may not be the source of your problem... of course it can't hurt to have them cleaned either... )
I think Aaron may be right about atleast the shitty idle/hard start... maybe it's time to drain the gas tank, flush it, and get some new fuel filters in there...?

Net Seven

iTrader: (5)

Fixed!!

It was the air flow sensor.

StarionX

Hey! I paid damn good money for my problems (please get in touch with my lawyers if you would like to inquire about getting a licence to share them).

Net Seven

iTrader: (5)

Ok, last night i was driving it home again and it doesnt feel to pull very strong. I was going up a hill and the rpms freeze at like 5.5k and dont go up any more until im over the hill. I also noticed that its hard to start it sometimes. Like it almost starts but doesnt, then i crank it a couple times and it starts up after i give it some gas while its almost started. This usually only happends when engine is still warm. Never had it happend in morning when car was cold.

Any ideas?

RylAssassin

Yeah i have a solution for you, toss the old ECU get a Haltech or similar, Get rid of the AFM Tune it and you should be all set.

yearrgh

How old is your fuel filter, and is yours an n/a or turbo. you're talking about your boost sensor, but they're talking about the 3800 rpm hesitation and your profile says you have a sport, which is n/a IIRC.

Manolis_D

iTrader: (2)

RylAssassin: Dude, the guy is randomly dumping stuff into his gas tank on a whim...you think he can install / program a Haltech?

-M