How do you know when it's time to change the injectors? I have 163K on my truck with the original injectors. I was told they should be changed every 80k miles? Is that true? Shouldn't I see signs of failure before changing.. and if there are signs what might they be..

Thanks!

GM recommends changing them every 100,000 miles. Big mileage drop is a good way to tell if they need replacing.

I've got sucky mileage since I've owned the truck.. 15.5 to 16.5mpg. Nothing's changed.. I also heard something about white smoke at startup? Nothing there either..

that isn't that bad of mileage. same as i get. i changed mine around 120,000, just thinkin that they should be old, but they really weren't. after the new bosch's were installed, no mileage or power gains were noted.

I'm running original injectors. 14-15mpg around town. 19-21mpg highway.

I was told not to fool w/ them unless MPG goes south and other factors are eliminated.

FWIW I was told the same thing on the timing set - which is also original - don't fool with it unless there is evidence of a problem.

Chaser

The nozzles wear slowly and the spray pattern drops off prime starting as early as 80,000 to 120,000 miles. Depends of course on usage highway/city driving and fuel quality.

Worn injectors increase black smoke on acceleration. If emissions "snap" tested (floored from idle) its the Opacity measure (particulate or smoke) is indicator of worn injectors. Also a tired IP and timing chain contribute.

Of course they will continue to work for good while longer but you should start saving for maintenance.

I have 254,000 miles with original injectors and timing set. I do notice some white smoke on start up, and also a puff of black smoke on downshift or hard acceleration. I am getting around 11 MPG city. IP is new. I think its time to change?

Do you suggest GM injectors, or an aftermarket company? How much should I expect to pay for parts?

Just curious why you didn't do injectors the same time you did IP since you were already right there? I bought some brand new Delphi's with installation kit for $250.

I bought the truck in January and it didnt run and sat for a year. It had 247,000 miles on it, and the guy I bought it from told me it needed the IP. I replaced the IP and wanted to make sure everything else worked good before I started throwing more cash into it. So far so good, nothing major has broke, barely anything at all

if one is going to replace the injectors, should I invest in the marine injectors that supposedly give ya 40more hp?

(obviously done after opening up exhaust and pryo)

if one is going to replace the injectors, should I invest in the marine injectors that supposedly give ya 40more hp?

(obviously done after opening up exhaust and pryo)

After extensive reading on this site I opted to buy new Delphi injectors. Read up on it and you will most likley make the same choice.

I got a new set of Delphis off E-bay for 300.00 with an instal kit, IP instal kit and injector socket. Also purchased a new 5521 IP for 480.00 ;)

if one is going to replace the injectors, should I invest in the marine injectors that supposedly give ya 40more hp?

(obviously done after opening up exhaust and pryo)

Reflash/rechip first after gauges & pipes, if that doesn't give you enuff grunt for yo money then do the HO injectors. I wasn't impressed doing it the other way round. HO injectors from my experience would be the last thing I would do after doing every thing else.

I've got sucky mileage since I've owned the truck.. 15.5 to 16.5mpg.

Don't know anyone that owns a gas one, do ya?

Don't know anyone that owns a gas one, do ya?
:exactly: What he said):h .

Don't know anyone that owns a gas one, do ya?

I know it's not REALLY bad and a lot better then the 9mpg the gassers get BUT talking to a F250 guy with a stick and he was getting 21mpg. I thought I'd get at least 19. Thinking back on this I must of been dreaming..

I installed the Heath PMD remote mount and was talking to them about future plans to get more spunk out of my truck. When he heard I had 160+K miles with original injectors he said he wouldn't do anything to the truck until I replaced the injectors. Said I'm in danger of an injector failing and destroying my motor. He also suggested the HO injectors. They were over $500 for the set.

That's why I started this thread. Hate when your buying parts from someone your starting to trust and then hear something like that.. Sort of scares you into making mods that wasn't on the short list.. Now of course if I don't change them and I blow my motor I'll be kicking myself cause I was warned.. :banghead:

I never knew this concern was even on the radar! What exactly is injector failure - spraying a stream of fuel onto the piston top?

Do injectors eventually suffer this fate just due to wear or is it more of a fringe incident?

Chaser

i used to work with a ford owner that said he got over 20 mpg. but when it came to it, he couldn't show it on paper.

I never knew this concern was even on the radar! What exactly is injector failure - spraying a stream of fuel onto the piston top?

Do injectors eventually suffer this fate just due to wear or is it more of a fringe incident?

Chaser
Exactly, there are many posts here about melted pistons due to bad injectors not allowing the fuel to atomize which will cause droplets of fuel to enter the combustion chamber which will in turn cause REALLY hot uneven flashes when combustion takes place.

ok anybody ahve instructions on how the heck to do this? Swapping injectors? And then purging the lines?

He also suggested the HO injectors. They were over $500 for the set.


Don't bother. You can get stock Delphis for under $300 with the clipless install kit.

Don't bother. You can get stock Delphis for under $300 with the clipless install kit.

Would this be from a reputable place or someone selling them off e-bay..?

Both. They are reputable and also sell off ebay. I bought mine from them and installed them Monday. They happened to be local here in Okc so I picked them up in person. You will notice that the bag has been opened when you get them but that's because for some reason Delphi sends them 10 in a package so they have to take 2 out.

Oh the name of the company is Delco.

Here is the link for the injectors...

http://cgi.ebay.com/ebaymotors/ws/eBayISAPI.dll?ViewItem&item=220010520700&ssPageName=MERC_VIC_ReBay_Pr4_PcY_BIN_Stores_IT

Both. They are reputable and also sell off ebay. I bought mine from them and installed them Monday.

Thanks! Did you need any special tools to do this or just a socket and some time..? I'm sure if I did a search out here this question has been asked at least once before.. :)

They have the Snap-on socket at the same site. Change out the glows while you're right there.

They have the Snap-on socket at the same site. Change out the glows while you're right there.

Does Advanced Auto Parts or AutoZone or someone have that socket in thier Loan-a-Tool lineup?

Chaser

Is it just a 30MM socket or is it a "special" socket.. :rolleyes:

Is it just a 30MM socket or is it a "special" socket.. :rolleyes:

I think it has a nut on the top so you can turn it with an open end wrench. It is also an "impact" socket.

Does Advanced Auto Parts or AutoZone or someone have that socket in thier Loan-a-Tool lineup?

Chaser

Don't know but if they do it would save me $30 or $40.