travis1911

Hello,

Today driving from work my engine was cutting in and out, especially when accelerating (but not exclusively). It was as if I as tapping the gas on and off constantly. Now, last time I had this issue, it was a fuel pump failure. This was around a year and a half ago. I made the mistake of getting it fixed at a shop where they put who know what pump in there. I was also told that there was rust in my tank that contributed to my pumps failure. So I figured I would drive it until I needed to address the issue again and actually fix the underlying issue. I guess now is the time.

I have a 1985 Toyota pickup in manual running a 22re. It has about 190,000 miles on it. It was my dad's and I have been using it as my daily driver to get me to school and back. I need help in doing this fix efficiently as I can't afford to get it fixed (college student). I have searched around these forums but the search function on this site seems to give me a bunch of threads that have nothing to do with my search words.

What I need help with:

How can I test the pump to see if it is actually the problem? I downloaded the FSM but it is over 1000 pages and I didn't see an index? Any help or link to someone explaining how to test the pump would be extremely helpful.

What pump should I get and where should I get it? I have done a little research on pumps and it seems that Denso is the pump of choice?

I'm thinking that I should just replace my gas tank as getting rid of the rust didn't work last time (this is when I was bringing the truck back to life after 11 years in my dad's shop). I took it to a guy that essentially had a high power pressure washer and he cleaned it out, but a little rust survived I guess. Is there a good way to solve the rust problem or should I just replace the tank? If I have to replace the tank, is there a brand that I should look for?

My throttle position sensor has been bugging me for a while, but it hasn't been giving me any huge issues. It cuts in and out at specifically 2100 rpm, so I just have been running it above or below that. Could this be accelerating my pump failure?

Any help is greatly appreciated.

-Sam

Terrys87

iTrader: (1)

85/86 trucks test port is different from the newer trucks. https://www.yotatech.com/forums/f199...l#post51760299 You will need to jumper like the picture in the link above. You can pull the fuel line off of the firewall while the key is on and see how much fuel is spraying out in to a container.

As old as the Throttle Position Sensor is, especially if it is original, I just replace them. They are just so worn.

As far as the gas tank, I would replace it if it has a lot of build up in it. It is not rust but it does look like rust. Each of my build threads, I show where I clean the tanks with white vinegar. It takes a while for it to clean it out but you can get shiny metal when the vinegar has cleaned. It takes a week or so for the vinegar to clean the tank. There are other ways of cleaning a tank located on the web.

When searching for information, use Google, Yotatech and what you are looking for. Each of the build threads in my signature has links to information that you are looking for if you want to spend the time looking at one of them. What you are going thru I have already done and tried to show it in my builds. Welcome to Yotatech.

travis1911

Thanks for your reply. I have been looking through your thread and it should be very helpful as I am ordering parts soon. Are there any brands for drop in tanks or TPS that you use/like?

Terrys87

iTrader: (1)

I have not bought any tanks. I have seen some complaints with most from what I see here on Yotatech from aftermarket. I am sure there is a good brand some where out there. Just make sure you can get it returned if it has issues. The crud in the tank is from chemical build up and is not rust. Any rusty tanks I have had is from mud sitting on top of the tank and rusting a hole thru the top.

I meant to mention earlier about the fuel pump. I get my pumps off of ebay and they are around $30 including shipping. If you can pop for the funds, I would go for a Denso. Toyota wants $300 for one and part stores are around $150 last time I checked. The $30 pumps I use have been great for me.

On the TPS, go with Denso. If you look on the TPS and can still see the part number on yours and it is the original TPS, Denso has since revised the TPS to a newer number from the last few I have bought. Usually your part number will cross reference to the new number and it will work great. There are a few threads on here on how to clean the contacts on your old TPS and I have had luck with it a few times but if it is original, I suggest replacing it.

When you get your new TPS, all it takes is a feeler gauge and a multimeter to get the gap set correctly. Sounds easy and it should be but I have a tough time getting the gap set correctly. I take my new TPS and Throttle Body to my local Toyota dealer and there is a mechanic there that knows these trucks well. They charge me 1/2 hour labor or around $30 for him to set it for me. There is not much that I take my trucks to shops for but sitting the TPS is one I will go to the dealer for. Make sure who ever sets you gap right knows what they are doing. Check it with the specs before leaving the shop.

I have a Factory Service manual. It is really popular on here for some to say to only use the FSM. Save yourself some time and money and get you a Haynes Manual. For the older trucks Haynes will work just fine for you. I have worn out one Haynes Manual and recently bought another one. I prefer my Haynes over the FSM. The FSM is a great manual but I have used it for 2 odd ball problems that I am not sure no one else has ever dealt with. One was a Wiper Delay and the other a Cruise Control issue. Other then rebuilding a manual transmission, Haynes will work great for you. Do not get a Chilton Manual. It is worthless.

travis1911

I'm starting to think replacing the tank is a bad idea. Maybe I would be better off just cleaning it out and seeing if I can salvage my current tank. The tanks insides have been exposed to the elements and it very well could be rust, but who knows what else is in there too. I want to get this problem sorted out but I don't know if a new tank is really worth it. I mean, who is to say the new one wont rust out?

I also am having a hard time figuring out which parts fit my truck. I think my truck is an 85 model (22rec EFI) but built in 84. Also, when I was looking for tanks most of them say "fit RN61, RN65, etc..." but my VIN says RN60? Anyways,

I think this pump will fit http://www.autopartswarehouse.com/sk...3-1606602.html but am not really sure.

The parts numbers on the TPS are really confusing as well, although I stumbled across a post on another forum that eluded to all m125 TPS being interchangeable so I got this one: Amazon seems to think it wont fit, but in the reviews one of the guys has it on his 85 4runner, so I figured it would work.

I have a Haynes and I love it, but the fuel tank section seems to be lacking.

Any thoughts on all of this?

Thanks again for all of your help.

Terrys87

iTrader: (1)

If your tank is good on top I would just clean it with vinegar if in no hurry to get it running, That pump that you posted the link to will work. It has all of the components that you need.

The quickest way to see which block you have is 85 and newer has a place for the fuel filter. 84 and older blocks are carb only.Since yours is fuel injected, you have a 85 or new motor. September or October is when they did the year model switch. Sounds like your truck was built late 84 which would make it an 85.

I never got all that RNxxx figured out on these trucks. It has been a long time but there is a website Toyotapartsonline or Toyota Overstock or something similar that can provide that information. I cant remember what the actual name is but they can tell you which TPS you need.

Terrys87

iTrader: (1)

The fuel system is pretty simple on these. With the above link I provided, it shows how to jumper the Fuel Pump. As long as you are getting power to the pump and a clean tank, that will test the tank. Normal operation is when cranking the motor, the Air Flow Meter activates the Circuit Opening Relay (located behind passenger speaker) then energizes the Fuel Pump.

I would be willing to bet that 7 out of 10 trucks on here have the Return Line clogged. The line running along the frame and the long "J" line on the Fuel Pump Bracket is most likely clogged. I have done several repairs on these trucks and clogged lines is really common on them. I show that in about each truck I have restored and is usually in the first part of my builds.

travis1911

I guess I'll have to make sure that line is clean when I put things back together. Okay, so I finally got the time to take a look inside the tank and it is real rusty. I think i'm going to replace it, unfortunately. Some things I would like your insight on.

Seeing as there is rust particles in the gas lines and on the fuel filter bracket, should those be replaced or would cleaning them somehow suffice?

Is there a good way to empty the tank? The Haynes manual makes reference to a drain plug, but I see no such plug. I tried taking off the skid plate below the tank and there are two bolts that prove to be too mighty for my 20v impact driver. I imagine the two lines coming back are return lines? could i just pop one off and run the gas into a tank with the engine on, or would that take forever?

This is turning into quite the job.