P0306 and P0300 (Cyl 6 & Random/Multiple Cyl Misfire) HELP A GIRL OUT HERE!

[97blazerct]

Ok.. To continue on my neverending problem....

SPECS: 1997 Chevy Blazer LS 4x4 with the 4.3 Vin W..

HISTORY: Everytime I go up a large hill.. Or when my truck rev's at approx 2000rmp's or higher.... This happens..
1. Start to lose power... Hit gas.. No power but engine revs higher.
2. Check engine light starts flashing
3. Truck starts to Bogg/diesel like it is going to stall
4. I lose all vacuum pressure to my brakes a-k-a NO BRAKES (way too scary for me!)
5. When I pull over and get it to roll to a stop... It continues to bog for a minute or so.. while the engine light flashes... Like its dying but has never actually fully died
6. Engine light goes solid, idle goes back to normal and i regain vacuum pressure...

CODE THROWN: This has happened about 10 times to me.. 7 or 8 were all on the same hill.. I've gotten 2 different codes.. Sometimes it is the P0306 - Cylinder 6 misfire and sometimes it is the P0300 - Random/Multiple cyinder misfire

HOW IT RUNS NORMALLY: idles rough sometimes, not bad.. I dont drive it very often because of this problem so that may be why... But overall she runs fine other then when I go up hill or on the highway at higher RPM's.

NEW PARTS/WORK DONE:
-Found dry-rotted vacuum hoses that might have been kinking... Replaced them tonight (and when I went up that hill, i still had the same problem/misfire)
-New plugs, wires, battary and basic tune up in OCt '04 but have only driven a few thousand miles since.
-New cap, rotor, fuel filter..
-oil changed regularly.
-New o2 sensors, Y pipe, exhaust....

Does ANYONE know what my problem could be? I'm DESPRITE and I am running out of ideas.. Has anyone who has had this problem FOUND A SOLUTION?!?!!?

Please please help me out... Email: [email protected]
Aim: Chevy4x4GiRRL

Thank you guys in advance

Christine

[97blazerct]

Also.. New Ignition Coil..

[dmbrisket 51]

how many miles? and in 97 it was a scfi fuel injection style, this style, not so much in blazers as some other gm vehicals with the same style injection, like to 'drop' an injector or two when pulling a grade (going up a hill) i suggest a cylender drop test on all 6 cylenders

[wafrederick]

It could be a worn out distribitor gear.The dstribitor has to be marked before pulling out,timing is not adjustable and has to be set with a scan tool.Are the new plug wires cheap ones,Cheap plug wires from AutoZone,Advanced will cause the miss.Cheap plug wires are not the way to go

[RahX]

Same with the cap, i've had cheap caps for those arc internally when under a load and that could cause some problems . Did it do this before your replaced this stuff or is it a new problem?