Well my computer froze so I hope I'm not double posting.

I have a 97 Blazer 4.3 with a fuel starting problem pump/regulator. Got the fuel pressue gauge reading was low. Thought it may be the fuel pump so I purchased one, than I went to the manufacturers website and found these informative videos and wanted to share. Hope it's OK to post a link. the videos areon the left side down abit DIY

I will be preforming additional testing before installling the pump, wish I went to these videos before buying.

How would you rate a Carter fuel pump, I know it's recommended to purchase a good quality over saving money on this part.

http://www.carterfueldelivery.com/fu.../consumers.php#

 

yeha but if you read the first post and subsiqent posts.. pressure isnt the problem.......[sm=sigh.gif]I wish it were THAT simple... I couldnt find the issues.. I ripped the harness out till i got to the driver side head.. wondering why I couldn't pull it out I guess that's where both left and right side harnesses go down towards the transmission and associated crap down there... so short of ripping the whole darn harness out.. I snipped the wires.. leaving enough to splice back together later if need be.. and spliced the oil pressure sensor according to the diagram tho oddly.. pin 21 grey vcm-a connector which i spliced to oil pressure sensor terminal C doesnt ring out to fuel pump relay terminal 5... they all NOW have 12 volts with key on.. but I'm wondering why this is... as far as the coil ground.. I left it as long as possible incase I have to resplice it to the original wire.. but put a ring terminal on it and i plan on mounting it to the ignition coil mounting stud along with another ground that will go right back to that clean ground spot on the front radiator support.. which again has a 0.0 ohm resistance to the negative battery terminal.. this all still sounds right.. so we'll see how it works in practice... I'll keep ya posted...

 

Oops sorry about that, I was really trying to just post the link, could have used it myself before. Thought is was pretty close to what you're posting about, but what do I know? It included fuel??

 

there's PLENTY of posts on here for people with fuel PUMP issues.. this one is more pertaining to electrical .... as you can see if you read the previous posts


*UPDATE*

k so got everythign back together.. and i stick the key in .. turn to on.. and wait.. no prime.. have it crank... oil pressure builds.. fuel pump relay now clicks with oil pressure switch...actually funny it wont prime when I jsut turn it on.. but if I LITERALLY let it turn for one to two revs... it while prime until I pull out the key...
*edit* after reading this I had to clarify^^^^^^


theres no prime with the key in the on position intially when I crank it the relay does click and you can hear the pump run as pressure builds like its supposed to... when I return the key to theon position from cranking back to the run position it will prime then cut off like its supposed to.....

if turn off then back on it will not prime but if I crank it 1-2 revs and the return to run it will prime.. ) kinda odd... hence the VCM question,,

*edit*^^^^^
but I STILL have no spark... I was hoping to avoid having to replace everything associated with the ignition... like I said before the coil TESTS fine... everything ohms out within range.. again no way to test the icm... OR vcm... so lets start a pool who's goin icm who's goin vcm...


stuff done

-new fpr
-new cap
-new rotor
-egr clean screen
-new acdelco plugs
-new bosch ultra premium wires( I KNOW AZ doesnt carry delco) and they were free (warranty)
-cut and conneted the oil pressure sensor switch terminal Cto pin 21 on the grey connector giving it now 12votls when pressure builds...
-cut and put ring terminal on the ground for the icm placed that underneath the IC stud along with a #12 ground that goes from that stud to the clean ground on the upper radiator support which has 0.0 ohms to the negative battery terminal... so again .. POOL.. ICM or VCM...
??????????????????????????????????????????

OH and one other thing.. vcm.. when they say it has to be flashed.. what gets flashed.. the VCM itself or the eeprom inside????

 

k well new stuff.. I found a vcm-a from a 95 jimmy slt with all the same options as mine... and it seems that the fuel pump relay issue has gone away but I think all this cranking and testing is wearing on the battery....

I used two flow charts... tho I don't know if they are applicable to my vehicle.. but here they are please read thru them as I have highlighted my issues.....

engine crank no start flow chart...

Step
Action
Values
Yes
No
1
Did you perform the Powertrain On-Board Diagnostic (OBD) System Check? N/A
--
Go to Step 2
Go to Powertrain On Board Diagnostic (OBD) System Check
2
Check the spark plug wires for open circuits, cracks or improper seating of terminals at the spark plugs, distributor and ignition coil before proceeding with the test.
Check spark at the plug with the J 26792 spark tester or equivalent while cranking. (If there is no spark on one wire, check a second wire). A few sparks then nothing is considered no spark.
Is adequate spark present?
--
Go to Symptoms
Go to Step 3< my situation..
3
Remove the coil wire from the distributor cap.
Insert J 26792 spark tester into coil wire and clamp the tester onto a ground. (used screwriver to stick in and test against good ground.... nothing!!)
Crank the engine.
Is adequate spark present?
--
Go to Step 12
Go to Step 4 **< my situation
4
Measure the coil wire resistance using a DMM. The resistance should be approximately the specified value.
Is the resistance within the specified value? SORT OF
1000 ohms/inch 8"-10" ~ 3.4k ohms
Go to Step 5 ***<<my situation***
Go to Step 30
5
Disconnect the ignition coil harness connector.
Probe the ignition coil connector terminal C with a test lamp connected to B+.
Crank the engine.
Is the test lamp flashing while cranking the engine? SLIGHT issue with this one.. I don't have a terminal C I only have A (white wire) and terminal B (pink wire) so I did the test with terminal a since it also splces to the tach wire.... and it DID flash when I had someone crank it
--
Go to Step 7 <<<my situation***
Go to Step 6
6
Turn OFF the ignition.
Probe the ignition coil harness connector terminal C with a test lamp connected to B+.
Is the test lamp ON?
--
Go to Step 27
Go to Step 8
7
Turn ON the ignition, with the engine OFF.
Measure the terminal A voltage with a DMM connected to a ground.
Does the voltage measure above the specified value?SAME thing SLIGHT issue.. I had to go toTerminal B and I did have the 12v(11.59V)
10.0 V
Go to Step 20 <<< my situation...*****
Go to Step 17
8
Turn OFF the ignition.
Disconnect the ignition control module harness connector.
Check for an open circuit between the ignition coil harness connector terminal C and the ignition control module harness connector terminal D.
Is the circuit open?
--
Go to Step 26
Go to Step 9
9
Disconnect the ignition control module harness connector.
Turn ON the ignition, with the engine OFF.
Measure the voltage on terminal A at the ignition control module harness connector with a DMM connected to a ground.
Does the voltage measure above the specified value?
10.0 V
Go to Step 10
Go to Step 18
10
Probe the ignition control module harness connector terminal C with a test lamp connected to B+.
Is the test lamp ON?
--
Go to Step 11
Go to Step 22
11
Disconnect the ignition control module harness connector.
Probe the ignition control module harness connector terminal B with a DMM set to the AC scale connected to a ground.
Crank the engine.
Observe the voltage while the engine is being cranked.
Is the voltage between the specified values?
1.0-4.0 V
Go to Step 19
Go to Step 14
12
Remove the distributor cap.
Check the cap for the following conditions:

 

just looking for any more insight......[&o]

*** update*** well yeah

looks like 4 out of those 5 modules I had were BAD!!!!!! only ONE after 10 tests still held up...

it was one of the junkyard ones.... the new one from autozone the previous owner put in was junk.. the original was junk... and 2 of the 3 i grabbed from the yard were junk... so now I have a KNOWN working icm and a good vcm(i think) we'll slap it back together tomorrow and get this thing hopefully concluded....

 

ok well icm tested from advanced auto parts.... check
vcm from 95 jimmy slt automatic 4x4.... check
new ignition coil from auto zone... check


it started... and ran .....


old coil reistance

primary -primary.......0.3ohms
each primary to secondary....8.8 ohms.....
each spot to metal body.... ofl

NEW coil resistance
primary-primary......0.6 ohms
each primary to secondary....8.9 ohms....
each spot to metal body.... ofl

anyone else see this as odd.... NO idea why it worked but it did.. I'll post in a week or so and follow up....


well it ran till it hit the first few bumps... the issue became more prevalent..

I got it back to the house.. and got it running again.. i wiggled the harness on the driver side... it died... 5 times in a row....so WIRING it is.. I FINALLY bit the bullet and ripped out the harness...

 

yeah after 5.5 hrs rippingout the harness ( that trans to engine bolt holding the clip is in THE most retarded spot....) it was a splice on circuit#9 the fuel pump oil pressure sensor relay.. it was completely rotted away.. so I spliced it back.... soldiered... silicone... heat shrink... and I also found the ground terminal to the vcm was mangled... so I cut and put on a new ring terminal... then went thru the whole harness... and soldiered every splice,.. then siliconed andelectrical tapedthem... ( this WILL not happen again)... then I took my time got everythign back together .. I also added a new #8 ground from each ground point on the heads... straight back to the battery... I will upload pix when I get back home.. dsl is too slow...

started up first try... and I went back under the hood wiggled every harness like a mad man... not a single sputter.. I think I finally have this one fixed....

thanx for the help kyle....

tho I knwo this wont be a common problem for everyones truck.. if you're finding an electrical issue and have tried everythin else.... you may have to bite the bullet and rip apart your harness......

and or the record i DID have to rip out the whole harness.. not only to get the the problem...( right at the "y" of the harness) but to make SURE this wont happen again and fix everythign while its out....

thanks again

now onto more important things.. like ball joints...lol and winshield washer..( failed inspection for those...) DOH!!!!

 

You be persistant!

Congratulations on solving the problem, and thanks for sharing.

 

I'm definitely glad you got it fixed Will! Good job! Wiring is not a fun thing for anyone and your persistence definitely paid off.