i was test driving a car that was recently tuned on neptune from synapse about 6 months ago in the summer. the car idles great and pulls nice. but once you get off the throttle and put it in neutral it stalls out. owner says its the tune or cold weather but idk what it could be.

car has a b18c with a jrsc @10psi. with percision 520cc injectors, walbaro pump, aem fuel rail, filter braided lines etc. plus it was tuned with that setup on neptune

hes cleaning the IAC to see if that helps. i thought that could be it but it idles good. plus its brand new

could it need a re-tune? after 6 months? could it be the hot weather tune driving in cold? or is it a fuel setup problem?

i googled it and found a coulpe threads on older software from neptune haveing random stalling but idk if thats what synapse used? i guess synapse doest tune with neptune anymore or thats what the owner said?????

if you can help or had similar problems let me know

 

I'm on neptune rtp and never had that problem. On my ls-v build I was on the free neptune and still never had that problem. What is the rpm at idle could it be to low? One of my buddys had that prob before and it was do to he's idle to low.. i just tuned the idle up for him and it has been fine since. I think his was at like 700-800..

 

Could be the idle setting or IACV duty cycle not being high enough. Fuel cut settings may also play a part. Contact another dealer if Synapse isn't offering it anymore, although they still have access so they are still able.

 

Sounds like IACV duty settings and/or fuel cut settings.

 

Yep, IACV duty/fuel cut x3. Car can't catch the quick drop in RPM when it activates idle mode, gets worse as it gets cold.

 

^^ plus 3

 

thanks for fast response;s


is the IACV duty settig in the tune? or can you adjust it without a tune?

car was tuned in hot summer and it was 10deg when i test drove it. pulled nice and idled fine. i will see what rpm it idles at.

could i get a re tune? or would i need a new tune? i will only drive the car in summer so would the tune be fine i summer? or only way to tell is trying it?

it made 210whp 170ftlbs on 10psi

 

forgot to add it had a lightweight flywheel installed after the tune.

and iacv is brand new same problem

could it be the tps sensor and map sensor pluged in wrong? anyone have pics or info ho to tell which is which? or does the flywheel drop rpms fatser than the stock flywheel?

 

The lightweight flywheel will definitely cause the problem you are seeing, without adjusting the tune a bit to compensate.

It wouldn't need a complete retune, it would just need a few of the idle settings and idle portions of the fuel/timing map adjusted to help smooth it out.

It could potentially go away just by raising the iacv duty cycle in the tune.

 

[QUOTE=mmcd;46592054]I'm on neptune rtp and never had that problem. On my ls-v build I was on NepTune EPROM and still never had that problem

lol im sorry i didnt know that one was called Eprom

but this guy knows his stuff.

 

ya it needs adjusting because of the flywheel like you said. i did some more searching and found it out.

.im going to bring it to xenocron most likley. maybe synapse if they will do it. or ccc

 

I can adjust the idle & air temp compensation, give me a call & let me know when you can get the car in.

 

would deleting the FITV cause the problem too? im going to take it to synapse soon. hopefully they can fix the problem

 

also forgot to mention that the car idles worse when its warm. once its warm it will not idle on its own. i have to give it throttle to stay running

 

why delete the fitv? put that back in and get the tune touched up and you will be set

 

the 70mm throttle body doesnt have a spot for the fitv. i hear of people deleting both the iac and fitv for hp.

i am going to mess with the throttle body idle screw, and check tps, ect, iac, iat with a volt meter. if they are all good its off to synapse because i dont know of anything else. other than tune related

 

B18C on 10psi only making 210? Something is wrong here

 

low reading dyno and a hot day. with no advance to ignition timing. plus its only a m62 supercharger check flow chart. superchargers are not for peak horsepower rather nice power band. useful rpm band. and a stock b18c with bolt ons is hitting 160whp if its perfect. thats a 50hp+ bolt on. about 1/3 of what the motor orig made. and it was dynod on a hot day. you can easily see +-10hp with a temp change.


i bet i can squeeze 250whp with water/meth injection retuned. and about 280whp with water injection and more boost 15psi+

210whp on a all motor is alot different than a boosted at 210whp. compare the dynos. boosted is making alot more power through entire rpm.

and anything over 280whp is too much for fwd imo. i like to drive my cars not spin the tires

 

can i get a retune with no fitv? or do i need it?

i know honda didnt use them for 96+ b18.

could i just compensate inside the tune for no fitv?

 

I love how you talk to me like I'm an idiot.
http://dynos.evans-tuning.com/catego...arch_type/and/

Plenty of cars making 230+ on 9-10 psi without meth or lht

 

read before you post. plus the dyno from gsr with 220whp/170tq is similar to mine. just bolt ons and jrsc 9-10psi.

every motor is different even if its the same model motor

a car can make 210whp on one dyno and 240whp on another. dynos vary


and i wasnt talking down to you. just read. research more. the info is there you just have to find it

 

lol ok. Gl with your car

 

thanks

and i fixed my car today.

the lack of a fitv caused it to idle funny once it warmed up and it would die if i let off the gas too quick in neutral. so i installed a 94-95 integra throttlebody and installed coolant lines. problem solved


heres a vid of what i experenced

http://www.youtube.com/watch?v=kRU_9...layer_embedded

 

I see that you have it fixed but you could go back to the larger throttle body. I have tuned a few jrsc cars over the years and my personal car is a jrsc. On one of the cars with a very light flywheel setup the only thing that would keep the car from dying was to open the throttle body just a hair farther, using the stop screw under the cable lever (having a brain fart dont know what else to call it). Anyways without a retune I would bet that your car will idle when hot and not die on off throttle.

 

my a/f ratio is great. runs perfect. cant complain about the tune. i originaly thought it was the tune. but i later found out the tune was good. i trouble shooted and found out that people who remove the fitv on 94-95 without retuning in cold areas have idle problems.

i know the throttle stop screw you were refering to. i adjusted it and my car would idle at 2k rpm. thats way too high. if i set it lower the car would just die. in the video his car atleast holds the low idle. mine didnt.

i could of ran without the fitv but i would need a retune so the iac knows i dont have a fitv anymore.

i figured this out by un hooking my friends 95 gsr fitv and he had same exact problem. so once i figured that out i used his tb on my car and bang it fixed my problem. i guess the fitv flows coolant into the iac at certain temps and it either sucks in air through the tb or out of it. 94-95 cars ecu thinks its there so it acts accordingly. so if you remove it from system it acts up.

where do you live? warm weather? i hear of people in fl and ca deleting the fitv with no problems. but its been cold here 10deg to 30deg