Very Hard "Cold" Start - 1994 S10 Blazer
#1
Very Hard "Cold" Start - 1994 S10 Blazer
HEy Everyone,
Wanted to first start by saying thank you! Been a long time lurker and finally decided to jump in. I have gotten a ton of info off this forum, and its been a huge help.
Hoping the experts can advise me here on what the problem is with my 1994 S10 Blazer. W Vin. 130k miles. I have replaced so far my ignition module, plugs, wires, filters, cap, rotor. Fuel Pump seems to be running fine. No smell of gas in oil. Runs great thru all RPMS, idles a tiny bit rough. Almost like a small miss at idle. No engine codes. I contributed the idle to just a high mileage vehicle.
My problem is that in the mornings, the thing takes sometimes up to ten trys to start. It will fire for a second, then die. Fires for a second, then die. It fInally coughs/stumbles thru the start and idles up, fine for rest of day. Im guessing fuel? Do you think I should just replace the spider? Does anyone have a link to the walk thru for the spider replacement. I was hoping I could get some hints on where to start throwing money at it. Love the truck, and its in great shape.
Thanks for the help guys!
Chris
Wanted to first start by saying thank you! Been a long time lurker and finally decided to jump in. I have gotten a ton of info off this forum, and its been a huge help.
Hoping the experts can advise me here on what the problem is with my 1994 S10 Blazer. W Vin. 130k miles. I have replaced so far my ignition module, plugs, wires, filters, cap, rotor. Fuel Pump seems to be running fine. No smell of gas in oil. Runs great thru all RPMS, idles a tiny bit rough. Almost like a small miss at idle. No engine codes. I contributed the idle to just a high mileage vehicle.
My problem is that in the mornings, the thing takes sometimes up to ten trys to start. It will fire for a second, then die. Fires for a second, then die. It fInally coughs/stumbles thru the start and idles up, fine for rest of day. Im guessing fuel? Do you think I should just replace the spider? Does anyone have a link to the walk thru for the spider replacement. I was hoping I could get some hints on where to start throwing money at it. Love the truck, and its in great shape.
Thanks for the help guys!
Chris
#2
Step #1 - Test the fuel pressure. It needs to be greater than 55psi and should remain above 10psi 10 minutes after the pump shuts off. If it doesn't go high enough or drops off too fast, you could be looking at a weak pump and/or a leak in the system somewhere.
#3
X2 on what swart said... Fuel press must be over 55. Seen it posted a few times.
#4
I have a 94 with the "W" VIN and mine done the same thing when I first purchased it. The EGR valve was clogged and I replaced it. Usually if it is the EGR it will run rough at idol but wil smoothen out when driving down the road. You may want to take it off and clean it. It is located under the thorttle body where the air intake hooks up. Mine is still a little slow to start when cold but if I pump the gas two times, it fires right up.
#5
Chris
I have a 94 with the "W" VIN and mine done the same thing when I first purchased it. The EGR valve was clogged and I replaced it. Usually if it is the EGR it will run rough at idol but wil smoothen out when driving down the road. You may want to take it off and clean it. It is located under the thorttle body where the air intake hooks up. Mine is still a little slow to start when cold but if I pump the gas two times, it fires right up.
Just a note on my pressure test. Sometimes when clicking the key to run and the pump cycles, it stops at 30 PSI, then I cycle the key again, and it will bump up to 50PSI before starting. Once I shut off, it IMMEDIATELY drops from 55PSI to 30, like within 1 second. Is a fuel pump in my future?Is that normal guys? Thanks!
Chris
Last edited by swartlkk; 03-22-2011 at 02:58 PM. Reason: *Combining Consecutive Posts* - Please use the EDIT feature to add additional information to your post and use the multi-quote feature to reply to more than one person.
#6
Sorry, that's 50psi and 10 minutes. Typo'd that one. You have a leak. I would suspect a problem in the plenum.
Also, please use the multi-quote feature when responding to more than one person. Consecutive posting is akin to double posting and is prohibited by the rules of the forum (#4).
Also, please use the multi-quote feature when responding to more than one person. Consecutive posting is akin to double posting and is prohibited by the rules of the forum (#4).
#7
Sorry, that's 50psi and 10 minutes. Typo'd that one. You have a leak. I would suspect a problem in the plenum.
Also, please use the multi-quote feature when responding to more than one person. Consecutive posting is akin to double posting and is prohibited by the rules of the forum (#4).
Also, please use the multi-quote feature when responding to more than one person. Consecutive posting is akin to double posting and is prohibited by the rules of the forum (#4).
Chris
#8
You first need to verify that the fuel leak is internal to the plenum. Fuel problems are a VERY well documented topic on the forum. A little searching goes a long way.
#9
I would say either the spider or the fuel pump. I have the EXACT same problem. You couldn't have described it better. In my case, I already replaced the spider and the problem still exists. I'm betting on the fuel pump now because I already know the sending unit is bad because the gas gauge reads 3/4 when I fill it. Also, I don't know if this helps or is relevant but my fuel pump doesn't make the humming noise I'm used to hearing on these trucks but instead makes a weird garbled noise. So yeah I would say check the injectors and the fuel pump. Let me know if you have any luck solving your problem! I plan on getting a new fuel pump when i get the money. Hopefully it will last until then!
#10
Have a very similar problem, but it only happens when starting in the morning. Once I get through that it fires right off the rest of the day seems sitting overnight is letting something get too cold. The weather is going to warm up soon so I'll see if it does it only when it's cold out at night or just because it sat all night. Replaced the fuel filter which seemed to have some effect but it's still was hard to start this morning. Put new cap and rotor on, AEM cold air intake, PCV valve and will change the plugs when they get here. Seems to be firing just doesn't seem to be getting fuel.