Jump to content

Bad mpg too

JF1957

Recommended Posts

JF1957 Enthusiast

JF1957

Posted
Posted

I replace my AC Delco plugs whit some Bosch platinum (no +2 or +4) and I notice a big difference on my fuel consomption, not on the good side lol. The pre set adjustement of the Bosch was about ,040 and I reajust them at ,060 like Chev said. Do you think that it can be the cause of my problem ? If it so I'll replace them whit the original one.

Question #2 Did anyone have a 1999 burb c2500 ? I would like to know how many spring leafs you got back there.

 

Regards

C & A s Dad Senior Enthusiast

C & A s Dad

Posted
Posted

We do not sell Bosch plugs so I am not familiar with the electrode. However, if they are made like the other plat plugs, you have likely damaged the center elctrode while you were gapping them. Most plats are not supposed to be re-gapped due to the high probability of damage.

 

Just a thought.

Giant Enthusiast

Giant

Posted
Posted

I hope this is not a hijack.

 

But i also have the same question pretty much. My plugs are old, but the engine runs fine. Could brand new plugs help fuel economy? or is that only when they start to miss and the engine run rough that new plugs will make a difference? Also, will adding non stock wires (the preformance ones with the bigger cores/lower ohms) harm/help the engine with OE plugs?

 

I'm going to be putting on new plugs and wires here in a bit. I'm putting on AC delco platinums for the plugs, but wasn't sure if moving to a better set of wires would make a difference at all.

 

thanks

95Sierra2500 Senior Enthusiast

95Sierra2500

Posted
Posted

It doesn't really matter what TYPE of Bosch plugs you use, they're garbage. I've never seen a GM vehicle that will run properly on Bosch Platinums, +2s, or +4s. I would suggest using at least Autolite plugs, NGK's, or AC Delcos. I wouldn't run Bosch plugs in my lawnmower, and I'm convinced it'll run on anything.

Hammer2785 Enthusiast

Hammer2785

Posted
Posted

I tried the Bosch plugs and will agree to them being absolute garbage. I only ran them for 6000 miles and my milage was down and performance down. I just replaced them with ACDelco and improvement was immediate. Also the CarQuest dealer said that the ACDelco are factory gapped at .040 and are supposed to be there and GM has changed the specs even on my 2000 from .060 to .040

C & A s Dad Senior Enthusiast

C & A s Dad

Posted
Posted

Robert, I replaced my plugs and wires about 6 weeks ago and went with Taylor Power Volt 8.2s. I did this primarily because I wanted Red wires and the Taylors are highly thought of. As far as perf. I can tell no difference in the seat of the pants. It does idle as smooth as warm butter. I can tell you that I have an Interceptor scan gauge that contains a HP calculation feature. Before the plugs and wires I had two runs, one at 298 and the other at 301. After the plugs and wires, I am at 309. I cannot say for sure the wires and plugs did this. The first run was on a 70 degree day and the second run with the new plugs and wires was on a 50 degree day. Either way, it runs great on the Taylors, they are great quality and look good under the hood.

 

David, you are right and your CARQUEST store advised you correctly. The AC plugs are pre gapped at .040 and are not to be re-gapped. NGKs are still gapped at .060 for some models and also are not to be re-gapped. My '02 model came from the factory with NGKs and that is what I replaced them with. The plug had NGK and the NGK # on one side and AC Delco and the long Delco # on the other side.

 

BTW Thanks for your business with CARQUEST. I have worked for them for 18 years.

Haulin' 8.1 Enthusiast

Haulin' 8.1

Posted
Posted

I just wanted to add a third professional opinion that Bosch Platinum plugs are garbage. I've never seen them work right. Many times when something comes into the shop with those plugs, they are the problem.

 

For fuel milage all you need is enough voltage to jump the gap at light load. If you don't have misfires now under WOT then lower resistance wires aren't going to help you at part throttle any. The thicker insulation is better protection though.

 

Vernon

pwall Senior Enthusiast

pwall

Posted
Posted
I can tell you that I have an Interceptor scan gauge that contains a HP calculation feature. Before the plugs and wires I had two runs, one at 298 and the other at 301. After the plugs and wires, I am at 309.

 

 

Sorry, not to hijake this thread, but....

C & S s Dad: have you calibrated the scan gauge for the HP or just using the default? I'm wondering if the default is good, or do I really need to take to it to a dyno to figure out? Thansk!

az'03Silverado Senior Enthusiast

az'03Silverado

Posted
Posted
It doesn't really matter what TYPE of Bosch plugs you use, they're garbage. I've never seen a GM vehicle that will run properly on Bosch Platinums, +2s, or +4s. I would suggest using at least Autolite plugs, NGK's, or AC Delcos. I wouldn't run Bosch plugs in my lawnmower, and I'm convinced it'll run on anything.

 

 

 

 

:cheers::chevy::lol::bs:

 

I've run them in several GM cars/trucks and they ran just as good as the originals. I didn't loose any MPG or performance. I had them in my '98 S-10 for about 50,000 miles without a bit of trouble. Also, my brother runs the +2's in his Alero and hasn't lost any performance. And he's at about 60,000 miles on 'em. I'm getting ready to put a set of +4's in my Silverado in a week or so. I'll give a report.

Oh, the gap on these is pre-set so re-gapping will ruin them.

Archived

This topic is now archived and is closed to further replies.

Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.4k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    342,840
    Total Members
    8,960
    Most Online
    appletrav
    Newest Member
    appletrav
    Joined

  • Who's Online   1 Member, 0 Anonymous, 501 Guests (See full list)

  • Latest Articles

  • Posts

    • newdude
      2 speed transfer case optional now?

      By newdude · Posted

      This is a 1/2 ton thing ONLY.  All HDs 2020-2026 have the two speed transfer case, with Autotrac as an option.     1/2 tons 2019-2026, regular 4x4s come with a single speed case (no 4LO!), and trucks with Z71 ordered, or all Trail Boss trucks come with the 2 speed case.  2 speed case is also an option on WT, and is also standard on High Country.  
    • newdude
      Different requirements for oil filters?

      By newdude · Posted

      2013 5.3 still to this day calls for the PF48 filter.  Which as a 15psi bypass pressure.     There is a TSB, 17-NA-157 that talks about the PF-63 and PF-64 filters which have a higher bypass rating of 22psi.    TSB HERE - temp.xml   "Beginning in 2012, the oil pumps began to regulate main gallery feedback instead of pump out pressure. This means that the oil pump now does not begin to regulate until pressure is built up to the main gallery. This change reduces the amount of time it takes to provide oil to the engine bearing and lifters during extreme cold start conditions.  Main gallery feedback oil pump control systems are present on the following engine families which use Spin-on oil filters: Small Gas Engine (SGE), Large Gas Engine (LGE), High Feature (HFV6) Gen2 and Small Block Gen5 gasoline engines. These engines with the main gallery feedback oil pump control systems are factory built with an ACDelco® oil filters"   It also calls out what engines use those filters.  The gen 4 small blocks were not on that list (LMG, LC9, L9H, L92, L94, L20, L96).  Gen 5 small blocks use the higher pressure filter.          That all said...   Your 7045 Napa filter is the PF63 equivalent, with 22psi bypass.  You are already using the higher bypass pressure filter.  You CAN keep using it, you don't technically have to use it though.  
    • Grumpy Bear
      Different requirements for oil filters?

      By Grumpy Bear · Posted

      Do you know WHY the filter relief setting was increased to 22 psig?    When the new system goes into the second stage the pump volume ramps up considerably. It was found that the 15 psi filter bypass setting put the filter in bypass on a warm engine when the second stage was activated. Raising the filter bypass setting forced the filter to do what it designed to do. Filter. Preventing debris from circulating during high load, high rpm operation.    So next question is how did GM find this out? VLOM/lifter failures and a deep dive by Melling Corp.    Last question. Is it required? Look at it like this; a motor may be equipped with a rev limiter. But it only works if the set point in reached. That 22 psig setting only matters if the pressure differential across the filter media exceeds 15 psig during normal warm operation. Second stage kicks in around 3000-3500 rpm.    I can't answer your question because I don't know you and how you use the truck. But I think there is enough information here to let you decide for yourself. 😉
    • Coastie05
      give me some tips to make my truck look better

      By Coastie05 · Posted

      Go back to OEM wheels. 
    • newdude
      2020 Trailboss 6.2 replacement

      By newdude · Posted

      Probably not their first rodeo, so it should go as planned most likely.  Typically the service manager or tech doing the swap will put some seat time to shake it down after they get it all put back together.  We usually put 50-100mi before we hand them back so if something happens, its not after you get it.  A coolant leaks, oil leaks, a ground left off or loose, vibration, etc.     The new engines so far have been good?  There's been a couple that have popped out there again (the replacement engine) but most have been okay.  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...