fuel injector replacement

[olhobbler]

I have a 1999 Limited 4wd with 279k. It has been extremely reliable up to recently. The engine shuttered while driving. First start up, it ran perfectly, however, after 15 min. or so, it ran on 5 cylinders. This was the pattern for 2 weeks. The tests always showed misfire cylinder 5. I swapped the coils around, put in new plugs, wires, and eventually coils..still the same misfire. Cylinders are 1,3,5 on passenger side..I figured fuel injector. Because it was cylinder 5..it only requires pulling the top plenum.
I am not a pro, but it was really pretty easy. It took me 2 and 1/2 hours. I bought gaskets but didnt even mess up the original one. The truck runs perfectly and is back to running great.

At first, i just slapped one in...but then i noticed grime,crud in the wells.
I cleaned 1,3 and 5 really carefully before installing the new injectors. They
seem to fit in place better with a clean well.

Most people would say why not do 2,4 and 6. Because it was 5, the job was somewhat simpler to do. Most shops seemed to want to do just the electrical fix..but that wasnt the problem..it was the injector. I could not allow my truck to labor and run on 5 cylinders any longer. If this describes your problem..order the injectors and gasket set..and go for it.

 

[xdnvrskinx]

What injectors did you go with?

 

[SplittingHairs]

My 2000 just had one injector die at 227,000 miles. It was cylinder number 4. I was successful using a factory Toyota injector

 

[gamefreakgc]

Yeah, I've swapped injectors a few times on the Toyota's I've owned. It's a very painless and simple job really, Toyota made it pretty easy to do.

Nothing beats saving money by doing the job yourself.

 

[kolelt]

As we speak. Tomorrow used OEM injectors should be coming in. I need to replace cylinder 3. However, I do believe some years have different fuel injectors.

 

[thecole1098]

As we speak. Tomorrow used OEM injectors should be coming in. I need to replace cylinder 3. However, I do believe some years have different fuel injectors.

Correct. The 96-98 has the silver/green injectors with 4 holes and in 99 they switched to the orange with 2 holes. I wouldn't recommend putting the incorrect ones in your model, it will upset the ECU.

 

[kolelt]

Correct. The 96-98 has the silver/green injectors with 4 holes and in 99 they switched to the orange with 2 holes. I wouldn't recommend putting the incorrect ones in your model, it will upset the ECU.

**** I ordered the wrong injectors for my 97! It was only $80 for used OEM. But still. GRRRRRR oh well.

 

[4bangr]

I wouldn't recommend putting the incorrect ones in your model, it will upset the ECU.

what's important is that you have a matched set of injectors, that all flow the same, and can meet your motors fuel needs. i have some 305cc Lexus injectors on my supercharged motor with a stock ECU; it runs beautifully.

after i went through some injector failures, i'll go out on a limb and say that a larger percentage of the surging/bad running issues on this forum will be injector related.

 

[kolelt]

what's important is that you have a matched set of injectors, that all flow the same, and can meet your motors fuel needs. i have some 305cc Lexus injectors on my supercharged motor with a stock ECU; it runs beautifully.

after i went through some injector failures, i'll go out on a limb and say that a larger percentage of the surging/bad running issues on this forum will be injector related.

I agree. INJECTORS ARE OVERLOOKED ! Now I ordered 6 OEM used injectors. But they are brown. And I just don’t feel like changing all the injectors. I might just end up buying a single new one from dealer.

 

[olhobbler]

injectors

i didnt know about diffferent injectors for the 3rd gen...i bought 6 new ones (not oem) off ebay for $65 bucks, used 3 of them on 1,3,and 5. I compared them to my old ones and seemed like a perfect match. After the job was through, it ran alittle rough for a minute..gradually adjusting and cleared up. It even starts better now. I have the other 3 new ones for future use if needed.
Will i regret not going OEM, not sure, but i am pretty satisfied with the results thus far.

 

[olhobbler]

ebay item#112170641181 I bought 6 new ones for 65.00. I put in 3 new ones..the other side are functioning and i left them alone. I wanted new ones..not refurbished or oem's that were cleaned up.

 

[olhobbler]

I broke open the troubled 5 injector..pulling off the two(2)hole plastic piece...it reveals 4 tiny holes..i guess thats the jet...nothing to really see..they looked clean..no sure why it was malfunctioning. As previously stated, i didnt know that the 97-98 had 4holes in the plastic piece.

 

[olhobbler]

since you are dealing with 3...are you going to do 1 and 5?

 

[kolelt]

Injectors don’t have to be clogged up to not work properly. There’s a a coil inside. Which can go bad after time. Thus causing malfunctioning of the injector. And no. I am not replacing 1 and 5. Because they are not broken or bad. Only cylinder 3 is. So that last what I am replacing. I just ordered a OEM injector for $140 shipped. OEM lasted over 200k. The others are still good. So OEM is the way.

 

[cccolin]

Interesting. Sounds like this might be my problem. I had the same thing but with cylinder 3. I replaced the spark plugs and it's better but still sort of doing the shudder thing.

 

[jasonochs25]

thread is only 6 months old. I figured I wouldnt catch too much hell for replying. I am about to replace the #4 cylinder online. this is the 3rd times its thrown a code p0304 inthe last 4-5 years, but this time, plugs and wires didnt fix the problem. I did order injectors and they are sitting on my counter...This original post was about the #5 injector, which I guess can be replaced without removing the plenum.How bad is the #4? I did order gaskets along with valve cover gaskets just because mine are leaking and I'll already be right there. How much of a pain, how long of a job. Its 108 here in the shade today and maybe mid 90s tomorrow, so hoping to start after the sun goes down. I cant have my car down monday morning any advice/info is very greatly appreciated!!!

 

[jasonochs25]

BTW, to all those that say these 3.4 lack power...drive it around a week with 5 cylinders and then complain when its back on all 6 hahaha

 

[CdaleR4000si]

thread is only 6 months od. I figured I wouldnt catch too much hell for replying. I am about to replace the #4 cylinder online. this is the 3rd times its thrown a code p0304 inthe last 4-5 years, but this time, plugs and wires didnt fix the problem. I did order injectors and they are sitting on my counter...This original post was about the #5 injector, which I guess can be replaced without removing the plenum.How bad is the #4? I did order gaskets along with valve cover gaskets just because mine are leaking and I'll already be right there. How much of a pain, how long of a job. Its 108 here in the shade today and maybe mid 90s tomorrow, so hoping to start after the sun goes down. I cant have my car down monday morning any advice/info is very greatly appreciated!!!

I had the P0304 last year, low resistance on the #4 injector. Rather than pay the $700+ that I was quoted to have it replaced, I decided to do it myself. After studying some write ups, I felt pretty confident that I could do it. I opted to go ahead and replace all 6 with injectors that had been serviced by Witchhunter. The injectors were surprisingly easy. It took probably an hour and a half to do all 6. Toyota did a pretty good job of keeping the intake removal very simple. I will say this though, when you remove the intake plenum, cover the openings in the lower intake so you don't drop anything in them.

Now, the valve cover gaskets, that is another story. Definitely not too difficult, but messy and time consuming. Luckily, I had those done recently, so I didn't have to worry about them. My understanding is that to do them properly, it can take a while. I, myself, would not start it on a Sunday night, if I needed it running on Monday morning (but I am not very experienced with this stuff).

I used this write up for the injectors...
https://www.yotatech.com/forums/f2/fuel-injector-removal-pictures-how-109389/

Read up on the valve cover job here...
https://www.google.com/search?ei=BX.......0...1.1.64.psy-ab..0.0.0....0.NYsbnzTvN3s

 

[jasonochs25]

thank you for the response. One thing...i was wanting to start on a saturday night and get done sunday or any time before monday. I do have ONE SERIOUS question that CAN save a ton of time...Can the upper and lower be removed together as one unit? All the videos Ive seen they split the two, but I dont see why. I can get to the center lower intake bolt if i remove a few things. So, Once again, thank you for the resonse and thank you for the input!!!

.

 

[jasonochs25]

I think i'll wait on the gaskets till I can for sure get them done in time.