# Help, Car running lean at idle **URL:** \ **Category:** SON240sx Automotive\ **Created:** [May 21, 2009, 7:35pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674 "2009-05-21T19:35:52Z")\ **Posts on this page:** 17\ **Page:** 1
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 21, 2009, 7:35pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/1 "2009-05-21T19:35:52Z")
ok so i changed oil and boosted up the battery. Started up the car, ran little loud because i have disconnected my exhaust system, but cat still there. Gas was on quarter since 5month but I put stabilizer before I stored it. Engine running quiet but AEM wide band reads 14.9-17.1. It used to idle on 14.7 ran for 5 min saw no change in reading, so i turned it off. anyone have an idea what it is :/: …? -exhaust disconnected …cat wont heat up fast. -Bad gas -injectors clogged Also here is my setup. rebuilt kA24DE with a few upgrades - Always run synthetic oil and Sunoco 94 - T3/T4 Hybrid Garrett Turbo - Tial 38mm Wastegate, custom recirc’d into downpipe - Walbro 255 LPH Fuel Pump - Vortec 8:1 FMU - stock injectors - 300ZX Fuel Filter - 2" Intercooler piping/silicone couplers/hose clamps - Custom EGR Recirculation - IAP & Megan Racing Downpipe - IAP Equal Length Manifold - IAP Stainless Oil Lines - IAP FMIC ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 21, 2009, 8:34pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/2 "2009-05-21T20:34:29Z")
definitely it’s fuel related man, check the timing and injectors, weird it’s acting like that if it was stored from 5 months even with the stabilizer in there…you’ve got a similar setup like mine, cept I haven’t installed it yet, I’m running a SR T25 tho on mine. I bet it might be better if your fill it up with some 15-25litres of fresh 94 sunoco, u running stock timing? ---
**Author:** ![Gt35r.com](https://avatars.discourse-cdn.com/v4/letter/g/dc4da7/32.png) [@Gt35r.com](https://forums.speedlife.net/u/Gt35r.com)\ **Post date:** [May 21, 2009, 8:47pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/3 "2009-05-21T20:47:12Z")
Drain that bad gas. Fill up with new gas, whats your fuel pressure at idle? ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 21, 2009, 8:51pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/4 "2009-05-21T20:51:15Z")
if anything, the FMU doesn’t regulate the increase of fuel pressure till it hits boost, so that wouldn’t be the culprit…rather the injectors and other fuel related things would be the problem, especially considering the lean idle. ---
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 21, 2009, 9:06pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/5 "2009-05-21T21:06:19Z")
Ye i will fill it up tomorrow, I just got sr injectors, would it be fine installing em without safc2.also engine n turbo was cold when i turned it off 😕 ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 21, 2009, 9:09pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/6 "2009-05-21T21:09:16Z")
with sr injectors, not really bro…if anything they’ll run more rich, u should grab or borrow a wideband to tune it properly along with the FMU, you’ll just need to work with the timing to get the A/F ratios right. That’s of course just using the FMU, aside from the SAFC. running rich is better than running lean for the time being but always take it easy if it’s not tuned well, especially if it’s lean cuz knock and detonation are trouble for the motor. With the injectors tho, I’d ditch the FMU if u ever plan to run over 8psi cuz it gets less reliable and useful. ---
**Author:** ![Gt35r.com](https://avatars.discourse-cdn.com/v4/letter/g/dc4da7/32.png) [@Gt35r.com](https://forums.speedlife.net/u/Gt35r.com)\ **Post date:** [May 21, 2009, 9:11pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/7 "2009-05-21T21:11:44Z")
> [@200 person fight at elmwood Regal](https://forums.speedlife.net/t/200-person-fight-at-elmwood-regal/22116/15): > > if anything, the FMU doesn’t regulate the increase of fuel pressure till it hits boost, so that wouldn’t be the culprit…rather the injectors and other fuel related things would be the problem, especially considering the lean idle. i didnt even realise he was running an FMU. An FMU still controls the flow at idle though. The other “fuel related problems” could be some what resolved if we knew the fuel pressure at idle. ---
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 21, 2009, 9:15pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/8 "2009-05-21T21:15:57Z")
I already have AEM wide band and had it running fine. I guess its the gas. I`ll keep an eye on temp. when running. ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 21, 2009, 9:16pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/9 "2009-05-21T21:16:12Z")
> [@Gt35r.com"](#): > > i didnt even realise he was running an FMU. An FMU still controls the flow at idle though. The other “fuel related problems” could be some what resolved if we knew the fuel pressure at idle. that’s not from what i know, FMU’s are pretty much mechanical diaphragms that with vacuum from boost create pressure to increase the flow of the stock injectors accordingly depending on the FMU, in this case 8:1 which is perfect for the setup, especially for only 7-8psi max. ---
**Author:** ![Gt35r.com](https://avatars.discourse-cdn.com/v4/letter/g/dc4da7/32.png) [@Gt35r.com](https://forums.speedlife.net/u/Gt35r.com)\ **Post date:** [May 21, 2009, 9:19pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/10 "2009-05-21T21:19:19Z")
correct! they are also known for failing though. ---
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 21, 2009, 9:22pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/11 "2009-05-21T21:22:41Z")
I dont have fuel reg. gauge ---
**Author:** ![Gt35r.com](https://avatars.discourse-cdn.com/v4/letter/g/dc4da7/32.png) [@Gt35r.com](https://forums.speedlife.net/u/Gt35r.com)\ **Post date:** [May 21, 2009, 9:24pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/12 "2009-05-21T21:24:27Z")
> [@where to get a nixon watch](https://forums.speedlife.net/t/where-to-get-a-nixon-watch/22117/7): > > I dont have fuel reg. gauge any local shop should be able to rent you a fuel press. test kit. Drain the bad gas first and see if that makes a difference. GLuck ---
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 21, 2009, 9:39pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/13 "2009-05-21T21:39:13Z")
will do. thanks bro ---
**Author:** ![redpotatoes](https://avatars.discourse-cdn.com/v4/letter/r/ecae2f/32.png) [@redpotatoes](https://forums.speedlife.net/u/redpotatoes)\ **Post date:** [May 22, 2009, 9:02am UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/14 "2009-05-22T09:02:54Z")
I wouln’t be too worry about running lean at idle. If you are running a good a/f at full boost, than you are all good. ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 22, 2009, 8:57pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/15 "2009-05-22T20:57:15Z")
^ true say, it’s when you driving it and it’s going through it’s paces when you should make sure your not running too lean. ---
**Author:** ![jdm-silvia](https://avatars.discourse-cdn.com/v4/letter/j/e19adc/32.png) [@jdm-silvia](https://forums.speedlife.net/u/jdm-silvia)\ **Post date:** [May 22, 2009, 11:14pm UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/16 "2009-05-22T23:14:09Z")
I changed my spark plugs, old once were gotted. poured some treatment and 94 octane and let it ran. started of lean (A/F) and came down. just need to get exhaust on and see how it goes during boost. ---
**Author:** ![RED\_LINE](https://yyz2.discourse-cdn.com/flex034/user_avatar/forums.speedlife.net/red_line/32/5656_2.png) [@RED\_LINE](https://forums.speedlife.net/u/RED_LINE)\ **Post date:** [May 23, 2009, 9:32am UTC](https://forums.speedlife.net/t/help-car-running-lean-at-idle/124674/17 "2009-05-23T09:32:46Z")
keep us updated man!