Chevrolet Repair: Rv with Chey 7.4l engine, vacuum leak, vacuum hose

Question
QUESTION: Hey Tom,
I diconnected the ecr valve, seem to make it want to stop running quicker. IF I take the ECR off can I  check it to make sure it working properly. One other thing when you are trying to keep it running if you try to give gas to fast it wants to spit back thru carb.

Joe Rivers

ANSWER: HI JOE,,YOU JUST THREW ME A HUGE CURVE BALL !!!! WHY YOU ASKED,IT SPITS BACK THREW THE [CARBURETOR] I THOUGHT THIS WAS FUEL INJ..OH BOY. ALL BETS ARE OFF NOW. I SHOULD OF ASKED YOU THAT LAST NIGHT. LETS START ALL OVER. YOU ARE NOT TAKING THE EGR VALVE OFF.[NOT ECR]EGR STANDS FOR [EXHAUST GAS RECIRCULATOR VALVE] LEAVE IT ON THE INTAKE AND REMOVE EITHER THE WIREHARNESS TO THIS VALVE OR REMOVE THE VACUUM SUPPLY LINE TO IT.WHICH EVER IT HAS. THEN TAP IT WITH A HAMMER NOT HARD TO CLOSE THE PINTLE VALVE,IF IT IS OPEN. THIS VALVE SHOULD BE CLOSED AT IDLE,IT OPENS UNDER ACCELERATION ONLY. YES YOU CAN REMOVE THIS VALVE TO SEE IF THE PINTLE VALVE IS STICKING.THIS VALVE SHOULD MOVE UP AND DOWN SMOOTH, SOMETIMES YOU CAN CLEAN THIS OUT 50-50 SHOT. IF IT IS STICKING GET A NEW EGR VALVE..HOWEVER BEING THIS IS A CARBUERTOR MODEL THIS SOUNDS LIKE A VACUUM LEAK..START IT UP AND PUT YOUR HANDS OVER THE TOP SIDE OF THE CARB,IF IT RUNS AND IDLES YOU GOT A VACUUM LEAK. IT IS GETTING OUTSIDE AIR FROM SOMEWHERE ELSE OTHER THEN THE CARB. LOOK AT MY LAST ANSWER TO CK FOR A VACUUM LEAK,WITH CARB SPRAY..

---------- FOLLOW-UP ----------

QUESTION: Hey Tom,

This is Throttle Body Fuel injection. I disconnected the Map sensor which has two connection to the intake manifold, it cranks and idles ok. map sensor 213-1545 ACDelco has a vacuum hose split to location on intake manifold. I have ordered another map sensor on Amazon(cheaper). next week delivery. Any thoughts

Answer
HI JOE,SO WE HAVE TBI, IT SOUNDS LIKE YOU FOUND THE PROBLEM,BY REMOVING THE MAP SENSOR AND ENG IDLES OK THIS IS MORE THEN LIKELY YOUR PROBLEM. THE MAP SENSOR THAT YOU HAVE ORDERED IS THIS A GM SENSOR ??? WOULD ONLY GET A GM SENSOR. I DO HAVE A QUESTION,YOU SAY YOU HAVE ORDERED ANOTHER MAP SENSOR. I DID NOT KNOW YOU HAVE REPLACED THIS MAP SENSOR IN THE PAST. DID I MISS SOMTHING ??? LET ME KNOW NEXT WEEK HOW YOU MADE OUT. HAVE A GOOD WEEKEND, IT FEELS LIKE I KNOW YOU !!! TOM..