i have a 98 cherokee 4.0 4x4 limited 220k miles
its running very rich DARL BLACK smoke from pipe when in good acceleration.. i cant find out how to fix this?!?! It idles terrible never dies but the engine shakes terrible when idling and my mpg has dropped by X3
replaced MAP sensor, IAC, TPS, 02 downstream sensor and upstream are new within 6 months , new cat and seafoamed the thing correctly... i've checked all the vacuum lines and they look fine. New injectors and spark plugs also
recently borrowed a fuel pressure gauge and while idling it jumped drastically from 40-50 in the same pattern as it idles bad
i'm thinking the fuel pressure regulator might be the cause but im exhausted of throwing money at it trying to find these problems
its running very rich DARL BLACK smoke from pipe when in good acceleration.. i cant find out how to fix this?!?! It idles terrible never dies but the engine shakes terrible when idling and my mpg has dropped by X3
replaced MAP sensor, IAC, TPS, 02 downstream sensor and upstream are new within 6 months , new cat and seafoamed the thing correctly... i've checked all the vacuum lines and they look fine. New injectors and spark plugs also
recently borrowed a fuel pressure gauge and while idling it jumped drastically from 40-50 in the same pattern as it idles bad
i'm thinking the fuel pressure regulator might be the cause but im exhausted of throwing money at it trying to find these problems