1996 4.3

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1996 4.3 - 1/10/2008 8:40:21 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline i have a 1996 chevy blazer with a 4.3 cmfi my problem is that its very had to start but starts right up with eather and has no power in passing gear or in the higher rpms sounds like its really boggy i checked the fuel presser its about 62 or 63 all the time replaced the iac valve the fuel pressure regulater tested most of the sensors lik the map tps iac (replaced) but still nothing is helping can any one else help? Post #: 1

RE: 1996 4.3 - 1/10/2008 9:11:32 PM    c0a8l0v6i8n9 Posts: 184 Joined: 1/6/2008 Status: offline Try cleaning the EGR valve. Also when was the last time you did a tune up? < Message edited by c0a8l0v6i8n9 -- 1/10/2008 9:17:21 PM > (in reply to cj599) Post #: 2

RE: 1996 4.3 - 1/10/2008 9:49:19 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline just did a tune up about 2000 miles ago new plugs wires rotor and cap (in reply to c0a8l0v6i8n9) Post #: 3

RE: 1996 4.3 - 1/11/2008 9:48:58 AM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline cleaned it dident do anything also after it warms up it starts fine (in reply to cj599) Post #: 4

RE: 1996 4.3 - 1/11/2008 11:24:43 AM    swartlkk Posts: 15276 Joined: 5/1/2005 From: Waterloo, NY Status: offline I would suspect a fuel issue...  Not fuel supply, but more quality and/or contaminant level (water, etc).  Maybe try a can of isoheat in the tank and see if that helps. _____________________________ Kyle- 04 Rainier My Restoration Projects Please Do Not PM for Tech Help (in reply to cj599) Post #: 5

RE: 1996 4.3 - 1/11/2008 12:00:24 PM    quinnman105 Posts: 601 Joined: 8/16/2007 Status: offline Good idea. That happened to me. I used dry gas and it fixed it. _____________________________ 2001 Chevy Blazer 4x4, 4dr 4.3L Vortec V6 (in reply to swartlkk) Post #: 6

RE: 1996 4.3 - 1/11/2008 5:28:06 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline just put a fuel pump in it today and fresh gas when i puled up to the filler it quit and now seems to be hydro locked (in reply to quinnman105) Post #: 7

RE: 1996 4.3 - 1/11/2008 6:55:58 PM    Hanr3 Wheels & Tire Moderator Posts: 3523 Joined: 5/11/2005 Status: offline pull hte plugs, crank the engine over and the gas will come out the spark plug holes. Careful, it is highly flammable. If you let it sit long enought he gas will drain intot he oil pan. Check your oil. Fuel pressure regulator is no doubt the reason for your leak/hydro lock. Takea a lot of fuel to hydro lock teh engine. as for starting when hot and not cold, check that IAC again. Also check for false air, a n air leak after the MAP/MAF. < Message edited by Hanr3 -- 1/11/2008 7:20:06 PM > _____________________________ "Some people spend an entire lifetime wondering if they made a difference. The Marines don't have that problem." -President Ronald Reagan '87 S10-Blazer - SOLD '93 S10-Blazer 4x4x4 - Sons DD, engine swap is done. '00 S10-Blazer 4x4x4 - My (in reply to cj599) Post #: 8

RE: 1996 4.3 - 1/13/2008 2:51:44 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline i gues ill tear it all apart again (in reply to Hanr3) Post #: 9

RE: 1996 4.3 - 1/13/2008 2:54:25 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline pulled the plugs yesterday then read your post i unpluged the fuel pump power wire and it started when u plug it back in it does the same thing it hydrolocks i guess ill try the old one (in reply to cj599) Post #: 10

RE: 1996 4.3 - 1/13/2008 3:07:28 PM    swartlkk Posts: 15276 Joined: 5/1/2005 From: Waterloo, NY Status: offline The fuel pump is not at fault if you are filling the engine with fuel... You have a fuel leak internal to the engine! Most likely culprit on a SCFI motor such as you have is the fuel pressure regulator. _____________________________ Kyle- 04 Rainier My Restoration Projects Please Do Not PM for Tech Help (in reply to cj599) Post #: 11

RE: 1996 4.3 - 1/13/2008 3:34:50 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline no **** i was clearing the engine out of fuel so it wouldent be hydrolocked so i unhooked the fuel pump so it would burn off the fuel in the engine                            now if i left it pluged in and pulled the plugs wouldent it still be pumping the manifold full of fuel???                                            and i dident have this problem untill i changed the pump              the reason i changed the fuel pump is that i noticed cold staring it was only pushing 35 psi < Message edited by cj599 -- 1/13/2008 3:44:43 PM > (in reply to swartlkk) Post #: 12

RE: 1996 4.3 - 1/13/2008 3:49:46 PM    TripleBlackBlazer Site Moderator Posts: 2004 Joined: 2/13/2007 Status: offline Sounds frustrating.  And it seems like your frustration is coming through in your posts and directed towards the people who are trying to help you.  I will say this, of all the technical and knowledgable people on here, NONE of them do well with language or being disrespected.  They are taking their own time to answer your posts, sharing the information they've learned over the years.  Take it easy on the language. Keep at it and try not to get too discouraged. _____________________________ (in reply to cj599) Post #: 13

RE: 1996 4.3 - 1/13/2008 4:07:33 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline i know im verry srry but i felt i was being disraspecked telling me its not a fuel pump issue on cold mornings the old fuel pump was pushing only about 35psi until it was running this hole thing is driving me nuts 2 weeks ago i put a fuel presser reg. in it to see if that was the problem and now i have to do it again and i already put a new iac sensor in it too < Message edited by cj599 -- 1/13/2008 4:13:57 PM > (in reply to TripleBlackBlazer) Post #: 14

RE: 1996 4.3 - 1/13/2008 4:19:09 PM    swartlkk Posts: 15276 Joined: 5/1/2005 From: Waterloo, NY Status: offline It seems we are having a difference of terms here. What do you mean by hydro-locked? Typically, the term hydro-locked is used to state that an incompressible liquid has filled one or more cylinders of the engine, preventing the engine crank shaft from rotating. We are trying to help here... _____________________________ Kyle- 04 Rainier My Restoration Projects Please Do Not PM for Tech Help (in reply to cj599) Post #: 15

RE: 1996 4.3 - 1/13/2008 4:27:48 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline yes that is what i meen the cyclenders are filled up with fuel i pulled the plugs unpluged the fuel pump and turned it over then put the plugs back in started it up and let it burn off all the fuel that had built up and tomaro im going to replace the fpr again and see if it helps and im really sorry for the cursing it just really frustrating i wonder if oriellys sold a foulty or different fuel press reg it was a little diff looking but it fit fine ill try it again (in reply to swartlkk) Post #: 16

RE: 1996 4.3 - 1/13/2008 4:32:29 PM    swartlkk Posts: 15276 Joined: 5/1/2005 From: Waterloo, NY Status: offline Ok. You know that there is a leak somewhere under the plenum. Now, here is how I would approach this. Remove the fuel lines from on top of the engine. Then remove the plenum. Reinstall the fuel lines and pressurize the fuel system, looking for leaks. It is possible that the o-ring on the FPR got pinched during assembly or something else completely unrelated. If fuel is pouring out of the FPR nipple, the FPR is completely at fault. _____________________________ Kyle- 04 Rainier My Restoration Projects Please Do Not PM for Tech Help (in reply to cj599) Post #: 17

RE: 1996 4.3 - 1/13/2008 4:35:43 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline yep that was exactly what i was thinking just remove the plastic cover and hook the lines up and turn the key on ill do that tomaro (in reply to swartlkk) Post #: 18

RE: 1996 4.3 - 1/14/2008 4:38:51 PM    cj599   Posts: 12 Joined: 1/10/2008 Status: offline turns out the oring on the pressure reg squeezed out one side shes all back togather running like a champ thank you very very very much (in reply to cj599) Post #: 19

RE: 1996 4.3 - 1/14/2008 4:41:52 PM    swartlkk Posts: 15276 Joined: 5/1/2005 From: Waterloo, NY Status: offline I knew it was going to be something like that!  Good job on getting it all fixed up! _____________________________ Kyle- 04 Rainier My Restoration Projects Please Do Not PM for Tech Help (in reply to cj599) Post #: 20

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