Hey guys ive been haveing some probs with my Truck which is a 89 S10 Blazer which i love. Anyway its been driveing super rough lately and even started jerking real bad on the freeway all of the sudden and the engine light came on and gave me the codes 32 and 33. One is the Map Sensor and the other is the EGR Valve.

Now before i go out and replace these anyone have any input??


Should i change both or just one??


Thanks

Bobby

 

I would start with the EGR valve. You should try to clean it, but be careful not to get any carbon cleaner on the vacuum diaphragm (rubber bladder on the large side of the valve itself. Once clean and moving somewhat freely, apply a vacuum and make sure that the valve opens and that the vacuum doesn't bleed down much over time. If it bleeds down, replace the valve.

Reason I say to do the EGR first is that it can cause a MAP code due to the large scale vacuum leak that a stuck EGR valve can cause.

 

K after looking at the EGR and asking the formal owner a few questions i decided to just replace the EGR. The Old one was in pretty bad shape. So i put the new one in and my truck ran great but after about a mile it slowly started acting up. Still does a little bit of jerking not as bad as it was. But when i come to a stop its on a extremely high idle 3000+ ( Im guessing because i have no Tack )

When i park and mess with the gas theres a slight hesitation.

Would the Map casue that?

Thanks
Bobby

 

High idle could be caused by a vacuum leak and/or a clogged idle air control valve (IAC) which is located in the throttle body.

Always try cleaning things before all out replacement. Cleaning is much easier on the wallet.

 

Anyone know what engine code 51 means??

51- calibration error, mem-cal, ecm or eeprom failure


I have no idea what it means

 

Only thing that my references say for this code is to check that all of the pins are fully inserted into the socket. If ok, replace the PROM, clear the memory, and recheck. If code 51 reappears, replace the ECM.

The PROM should be under a cover that is held onto the ECM by two or three screws. The PROM is a computer chip that contains all of the instructions for keeping the engine operating properly. If it has come dislodged from its socket, it may cause this code.

 

well after doin all this work to it i forgot to unplug the battery so it could reset. I did that and drove around the neighborhod and ran fine but we will see when i drive into town to work in the morning.

 

Code 32 (EGR) iscommon with Blazers with high milage on the odometer or those that may have worn out valve seals.Hardened and leaking valve seals is a sore spot with the Chevrolet 4.3L V6 engines, even ones with less than 50,000 miles.I feel like that is about 80% of theoil consumptionproblem withmy '91 Blazer. The ECM will turn on the SES light after5 to 10 milesofdriving above 65 MPH. That is caused byclogged EGR passages in the intake manifold which in turn causes the pentel in the EGR valve to stick. Just cleaning or replacing the EGR valve willtemporarilyfix the problem. To get a more permanent solution,you should also clean out the carbon build-up in the EGR passages in the intake manifold.

Remove and clean the EGR valve with brake cleaner and then cut offa 18" peice of old speedometer cable and chuck it into a drill motor and spin it in the EGR passages in the intake manifold to break up the carbon deposits.That will perform the samefunction as aplumber's sewer snake. Use a shop vacuum or equal and suck out the broken up carbon deposits in the intake manifold EGR passages.

The get a more lastingsolutionto eliminate the SES code 32 light before I rebuild myengine, I purchased a 1991 TBI intake manifold for $75 ata auto salvage yard, cleaned it thoroughly, painted it black and replaced my original manifold with the clean one. That should last until I can rebuild the engine. When the heads are rebuilt,my machinist will install positive stop teflon valve seals and K-line phosphor-bronze valve guide liners.

The K-line or Hastings or equal phosphor-bronze guide liners are "self-lubricating" and are absolutely necessary when using thepositive stop teflon valve seals. That isbecauselittle or no oil will get past the teflon sealsto lubricate the valve stems. If you usethe original cast iron guides with the teflon seals,lack oflubricationwill result ingalledvalve stemsand stickingvalves, even if the valves have chrome stems. When rebuilding the cylinder heads, never use thefailure prone factory style rubber or neoprene umbrealla seals. The original factory umbrealla style valve seals only lastuntil the vehicle gets out of the 30,000 mile warranty. Right on schedulejust over 30,000 miles, my 1993 Sonoma started blowing smoke out the exhaust pipe every time I started the engine after it sat for a few hours.