97 Chev Blazer Fuel/Injector Problem? HELP

Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code.

Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools.

Mav

Reply to
Mav
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I did receive a P0300 code over the last month which is ...... multiple/random cylinder misfire

As I said before: Items Replaced this week.....

Fuel filter Fuel pump/unit in gas tank.. Ignition Coil Rotor Distributor Plug Wires Plugs/ A/C Delco Platinums OE specifications

Timing Chain ( 4 months ago)

Fuel pressure with pump on and engine off is between 60 - 66 psi...Pressure holds steady after pump turns off.....

Vehicle will run if I directly pour gas Carefully into the throttle bore

Vehicle is getting spark to plugs

Vehicle does start up some times but stumbles to stay running until it shakes to death and stops....(mostly because of fuel starvation)

**MOST LIKELY CULPRIT***

Something with the vehicle starving to death by not getting fuel......

Injectors not working Injector controller not working Some sensor not working that controls fuel deliver somehow but doesn't flag a code.....( as I have none flagged)

Reply to
Mav

====================== You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.

Reply to
Scott M

Top post Why not save yourself some head ache .... Test the injectors for pulse with your test light.. If they all pulse then pull the damn fuel rail to see if the injectors are clogged....Its just that simple........ Your trying to put more work in it than its worth.....You dont need to test every sensor in the truck for christ sakes.....The fuel system isnt this complicated...Pull out the injectors if they pulse......their probly all gummed up... Steve C

Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 12:25am (CST+6) From: snipped-for-privacy@no.com (Scott=A0M) "Mav" wrote in message news:b%dWb.102007$ snipped-for-privacy@twister.tampabay.rr.com... Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code. Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.

Reply to
S C

Yeah it runs or tries to run at around 650 or so( The scanner says what it should run at right below what the actual is and it tries to keep it there ) .... I have the Auto X-Ray 6000 handheld scanner we just got in 4 weeks ago. I noticed multiple cylinder misfires on 1 and 2 a couple of weeks ago when I got the P0300 code. I thought it might have been the ignition, plugs, wires,,ect... but I replaced all of them and that wasn't it....

Reply to
Mav

Have you pulled the Sequetial fuel injection system on a blazer? It's not anything even close to being remotely fun or easy. Testing sensors isn't hard, knowing what the output is suppose to return is the question. Sorry I have the patience to do these tasks, I just don't pull and yank if not needed. That's what the dealership does!

I will however try the test light on each of the six injectors when I make a nice little probe to jam into the connector tomorrow.

Okay, any other suggestions on how to test things.....

Re: 97 Chev Blazer Fuel/Injector Problem? HELP

Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 12:25am (CST+6) From: snipped-for-privacy@no.com (Scott M) "Mav" wrote in message news:b%dWb.102007$ snipped-for-privacy@twister.tampabay.rr.com... Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code. Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools. ====================== You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.

Reply to
Mav

Seems useless but here we go.... Yeah I have done many..Most of them after people like yourself misdiagnose in the first place and have already changed too much crap they didnt have too.....Also if it was in my stall in my dealership it would have already been fixed......Point of the matter is you dont even know if your getting pulse out of the injectors..Which a simple noid light at your local parts store isnt that expensive.You noticed you had a miss and thought it was plugs wires etc...Why didnt you run any tests then to see if you were getting fire...Or run a continuity test on the wires to make sure you didnt have and open before you just changed them out.....you have a misfire in cylinders 1-2-3 right......But are all of them true misfires? I believe you only have a true misfire on cylinders

1 and 3 and #2 is just a bleed over..Your starving for fuel but you seem to be missing on the basic fuel system diagnostic...You have fuel pressure correct the fuel pump relay kicks in and out correct....you dont know if your injectors are getting pulse to cylinders 1,2,3 which are misfiring....Which if you are everyone is telling you that it is more than likely the injectors....But you want to test everything else???????? WHY Obviously your getting fuel to the injectors so why isnt it comming out? They are not pulsing or they are clogged .......Its not rocket science...Its basic fuel diagnosis...Oh by the way knowing the output to the injectors isnt a problem if the testlight lights up the the injector should open...That is UNLESS ITS CLOGGED!!!!!!!!!!!! Steve C

Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 2:24am (CST+6) From: snipped-for-privacy@cfl.rr.com (Mav) Have you pulled the Sequetial fuel injection system on a blazer? It's not anything even close to being remotely fun or easy. Testing sensors isn't hard, knowing what the output is suppose to return is the question. Sorry I have the patience to do these tasks, I just don't pull and yank if not needed. That's what the dealership does! I will however try the test light on each of the six injectors when I make a nice little probe to jam into the connector tomorrow. Okay, any other suggestions on how to test things..... "S C" wrote in message news: snipped-for-privacy@storefull-3357.bay.webtv.net... Top post Why not save yourself some head ache .... Test the injectors for pulse with your test light.. =A0=A0If they all pulse then pull the damn fuel rail to see if the injectors are clogged....Its just that simple........ Your trying to put more work in it than its worth.....You dont need to test every sensor in the truck for christ sakes.....The fuel system isnt this complicated...Pull out the injectors if they pulse......their probly all gummed up... Steve C Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 12:25am (CST+6) From: snipped-for-privacy@no.com (Scott M) "Mav" wrote in message news:b%dWb.102007$ snipped-for-privacy@twister.tampabay.rr.com... Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code. Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.

Reply to
S C

Finally somebody with a answer! I changed the other items out because I had them to change out any ways and purchased them 2 months ago but didn't feel overly rushed to put them in just yet. I changed the fuel pump assembly because the gas gauge hasn't worked for the last 15,000 miles. The truck broke down at my brothers place when he borrowed it last weekend, so I haven't had but one day to replace the stuff I had anyways to see if that changed anything. It didn't, so I have all week to get possible suggestions till I go back. So this next weekend I will have all my tools to do the easy things, like you said (test light). But not everything is so cut and dry or everybody would be a mechanic. So asking to see if anybody has any suggestions after the easy ones don't work is always a good idea. If it was in your stall at your dealership you also have all the tools right there, books, schematics, and the sort. Your also a mechanic apparently so I would hope you should have some clue otherwise it might be time to find another line of work.

Also what is odd is that all the plugs that I changed were way over rich, charcoal black. Which if the injectors were starving they would look lean. But they all looked like they have been running rich. Not exactly something I would think is the norm for one or two injectors getting clogged. Why would all six injectors be running rich.... something esle is also going wrong. Unless it goes into some sort of limp mode or rich mixture mode to get by with the other injectors running lean or not at all. Which makes me wonder why I don't get a lean flag on the the 02 sensor, or any other codes. I guess we'll find out this weekend when I go back to dig into the beast.

Mav

Seems useless but here we go.... Yeah I have done many..Most of them after people like yourself misdiagnose in the first place and have already changed too much crap they didnt have too.....Also if it was in my stall in my dealership it would have already been fixed......Point of the matter is you dont even know if your getting pulse out of the injectors..Which a simple noid light at your local parts store isnt that expensive.You noticed you had a miss and thought it was plugs wires etc...Why didnt you run any tests then to see if you were getting fire...Or run a continuity test on the wires to make sure you didnt have and open before you just changed them out.....you have a misfire in cylinders 1-2-3 right......But are all of them true misfires? I believe you only have a true misfire on cylinders

1 and 3 and #2 is just a bleed over..Your starving for fuel but you seem to be missing on the basic fuel system diagnostic...You have fuel pressure correct the fuel pump relay kicks in and out correct....you dont know if your injectors are getting pulse to cylinders 1,2,3 which are misfiring....Which if you are everyone is telling you that it is more than likely the injectors....But you want to test everything else???????? WHY Obviously your getting fuel to the injectors so why isnt it comming out? They are not pulsing or they are clogged .......Its not rocket science...Its basic fuel diagnosis...Oh by the way knowing the output to the injectors isnt a problem if the testlight lights up the the injector should open...That is UNLESS ITS CLOGGED!!!!!!!!!!!! Steve C

Re: 97 Chev Blazer Fuel/Injector Problem? HELP

Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 2:24am (CST+6) From: snipped-for-privacy@cfl.rr.com (Mav) Have you pulled the Sequetial fuel injection system on a blazer? It's not anything even close to being remotely fun or easy. Testing sensors isn't hard, knowing what the output is suppose to return is the question. Sorry I have the patience to do these tasks, I just don't pull and yank if not needed. That's what the dealership does! I will however try the test light on each of the six injectors when I make a nice little probe to jam into the connector tomorrow. Okay, any other suggestions on how to test things..... "S C" wrote in message news: snipped-for-privacy@storefull-3357.bay.webtv.net... Top post Why not save yourself some head ache .... Test the injectors for pulse with your test light.. If they all pulse then pull the damn fuel rail to see if the injectors are clogged....Its just that simple........ Your trying to put more work in it than its worth.....You dont need to test every sensor in the truck for christ sakes.....The fuel system isnt this complicated...Pull out the injectors if they pulse......their probly all gummed up... Steve C Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 12:25am (CST+6) From: snipped-for-privacy@no.com (Scott M) "Mav" wrote in message news:b%dWb.102007$ snipped-for-privacy@twister.tampabay.rr.com... Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code. Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools. ====================== You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.

Reply to
Mav

. . . INLINE.... (comments in parenthesis...by marshmonster) Wed, Feb 11, 2004, 2:24am (CST+6) From: snipped-for-privacy@cfl.rr.com (Mav)

Have you pulled the Sequetial fuel injection system on a blazer?

(nope)

...... It's not anything even close to being remotely fun or easy.

(sorry)

.... Testing sensors isn't hard,

(I agree)

.... knowing what the output is suppose to return is the question.

(on...off..on..off...on..off....is the answer)

..... Sorry, I have the patience to do these tasks, I just don't pull and yank if not needed. That's what the dealership does!

(you really oughta left that one out if you ) (were wanting serious advice....now yer) (likely to be told to use a left handed) (noid light)

...... I will however try the test light on each of the six injectors when I make a nice little probe to jam into the connector tomorrow.

(jest out of curiousity.....why don't yuh jest) (go on down to the AutoZonedOut store) (and buy yerself one of them Noid lights) (fer around $8 and jam IT in there??)

.... Okay, any other suggestions on how to test things.....

( USE A NOID LIGHT............ AND POST THE RESULTS.... like you were told to.... or.....do it yer way)

marshmonster thinks yer a funny little parts changer...oops.... mechanic.

~yuh can give em a wrench...but yuh can't make em turn it~ ======= =======

Reply to
Marsh Monster

(top Post) This is why we need to see if the injectors are pulsing...To determine weather or not to exclude the fuel system for now..If they dont pulse they we need to find out why..you need to check in your pcm for past codes they are stored in the history..The codes may not came back because it wasnt started long enough for the Pcm to detect a problem in the last ignition cycle.....But will be in the history.....We need them codes if your scanner cant get them you need to find ne that will.....To get the history codes will bring us closer to the root of the problem from when it started.....For some reason I thought you were a mechanic of some sorts....By the way you came on with the problem and said what you have already done. the P0300 may be the only active code but you need to pull a history if you havent already cleared them by mistake....

Steve C

1 and 3 and #2 is just a bleed over..Your starving for fuel but you seem to be missing on the basic fuel system diagnostic...You have fuel pressure correct the fuel pump relay kicks in and out correct....you dont know if your injectors are getting pulse to cylinders 1,2,3 which are misfiring....Which if you are everyone is telling you that it is more than likely the injectors....But you want to test everything else???????? WHY Obviously your getting fuel to the injectors so why isnt it comming out? They are not pulsing or they are clogged .......Its not rocket science...Its basic fuel diagnosis...Oh by the way knowing the output to the injectors isnt a problem if the testlight lights up the the injector should open...That is UNLESS ITS CLOGGED!!!!!!!!!!!! Steve C Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 2:24am (CST+6) From: snipped-for-privacy@cfl.rr.com (Mav) Have you pulled the Sequetial fuel injection system on a blazer? It's not anything even close to being remotely fun or easy. Testing sensors isn't hard, knowing what the output is suppose to return is the question. Sorry I have the patience to do these tasks, I just don't pull and yank if not needed. That's what the dealership does! I will however try the test light on each of the six injectors when I make a nice little probe to jam into the connector tomorrow. Okay, any other suggestions on how to test things..... "S C" wrote in message news: snipped-for-privacy@storefull-3357.bay.webtv.net... Top post Why not save yourself some head ache .... Test the injectors for pulse with your test light.. If they all pulse then pull the damn fuel rail to see if the injectors are clogged....Its just that simple........ Your trying to put more work in it than its worth.....You dont need to test every sensor in the truck for christ sakes.....The fuel system isnt this complicated...Pull out the injectors if they pulse......their probly all gummed up... Steve C Re: 97 Chev Blazer Fuel/Injector Problem? HELP Group: alt.trucks.chevy Date: Wed, Feb 11, 2004, 12:25am (CST+6) From: snipped-for-privacy@no.com (Scott M) "Mav" wrote in message news:b%dWb.102007$ snipped-for-privacy@twister.tampabay.rr.com... Airflow???? Hmmm isn't that one of the things on the air intake hose? I know there is another thing for air inlet temperature and the other I think is the Mass Airflow Sensor....That's a thought....but I would think it would flag a code. Doesn't anyone have a Helms Manual in this group? I need the one with the sensor trouble shooting in it like I have for my old 89 K5. I need to just buy them, it gives trouble shooting trees and sensor readings for output using the multimeter or other tools. =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D You can eliminate the MAF by unplugging it. It will go into limp in mode and should run. Also check with your scanner to see if it shows correct RPM while you run it on carb cleaner.
Reply to
S C

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