Dead fuel pump?
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rdruss
Senior Member
Check your fuses. I think there's a fuel pressure shrader valve for hooking up a pressure gauge, or just remove fuel supply at the rail and crank and see if any fuel. Crazy stuff can happen on electronic engines and you can start throwing all kinds of parts at it with no success. I watch a youtuber: "Pine hollow auto diagnostics", Ivan is an expert at diagnosing problems like this and it's surprising how many are just frayed wires and other similar maladies.
How do you check for spark? Pull a plug out and ground it and look for spark like with a chainsaw?
Hungryhawk
Member
You can try to identify wires to fuel pump and use multimeter to investigate.
I read somewhere some years have a removable panel above fuel tank, under the carpet. Other years you can carefully cut an access panel.
Might be easier than dropping fuel tank to get at fuel pump.
I agree your fuses, wiring and perhaps relay? Need careful examination
I read somewhere some years have a removable panel above fuel tank, under the carpet. Other years you can carefully cut an access panel.
Might be easier than dropping fuel tank to get at fuel pump.
I agree your fuses, wiring and perhaps relay? Need careful examination
One question while I'm thinking about it:
How do I silence all the stupid bing bing bong bong sounds the car makes, like when turning the key to acc?
Is there a speaker I can disconnect? I have aftermarket stereo so I do not think it's routed through the radio speakers.
Makes it hard to listen for a fuel pump when the car is playing the song of its people.
How do I silence all the stupid bing bing bong bong sounds the car makes, like when turning the key to acc?
Is there a speaker I can disconnect? I have aftermarket stereo so I do not think it's routed through the radio speakers.
Makes it hard to listen for a fuel pump when the car is playing the song of its people.
AuSeeker
Elite Member
That's a good question that I have no real answer for, to do a old school check for spark you would have to remove the coil and spark plug, reconnect the plug to coil and ground the plug to look for a spark, but with a coil for each cylinder I'm not sure that will work, I guess one way is to try it...but if you don't get a spark you really wouldn't know if it because of the coil and plug not being installed or if indeed you have no spark, I'm guessing that a good scanner would tell you if you're getting spark or not...BUT also if you weren't getting a spark it should trigger the check engine light and throw a code.
Edit: I just got this from a web search....
"If an engine isn't getting a spark, it will likely trigger misfire codes (P0300-P0308), and possibly ignition coil circuit malfunction codes (P0350-P0362) or specific coil fault codes (P2300-P2311), depending on the cause. These codes indicate that one or more cylinders are not firing correctly due to a lack of spark."
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Looks like I found the problem. Not a fuel pump.
Hooked up my scanner to pull codes, got a crankshaft position sensor code, starting examining the wiring and found this:
I'm assuming this is the CKP sensor wire. This is now the third time I have had one of my cars disabled from mice eating wires. Sucks.
I can easily repair this but I'm not sure:
- Where does it route to?
- What all do I need to remove to access it?
Hooked up my scanner to pull codes, got a crankshaft position sensor code, starting examining the wiring and found this:
I'm assuming this is the CKP sensor wire. This is now the third time I have had one of my cars disabled from mice eating wires. Sucks.
I can easily repair this but I'm not sure:
- Where does it route to?
- What all do I need to remove to access it?
UPDATE: This repair is an absolute NIGHTMARE.
After an hour of struggle I was able to remove one end of this harness and clean it up:
This harness is for the AC compressor and I think (but cannot confirm) the CKP sensor.
Unfortunately, I'm at an impasse. Here is the other end (look just below exhaust manifold):
I've unhooked a couple things like evap and moved some vacuum lines out of the way.
Unfortunately, there is NO ACCESS to this area. None. I can't fit even one hand down there, I can't fit a tool down there. There is zero clearance to detach this wiring bundle, and even if I could there isn't enough slack to get it up into a place where I can work on the wiring. In addition there are other wires either damaged or severed, but I can't tell from my vantage point.
Unless someone knows a trick to accessing this harness, I think this is going to the shop.
After an hour of struggle I was able to remove one end of this harness and clean it up:
This harness is for the AC compressor and I think (but cannot confirm) the CKP sensor.
Unfortunately, I'm at an impasse. Here is the other end (look just below exhaust manifold):
I've unhooked a couple things like evap and moved some vacuum lines out of the way.
Unfortunately, there is NO ACCESS to this area. None. I can't fit even one hand down there, I can't fit a tool down there. There is zero clearance to detach this wiring bundle, and even if I could there isn't enough slack to get it up into a place where I can work on the wiring. In addition there are other wires either damaged or severed, but I can't tell from my vantage point.
Unless someone knows a trick to accessing this harness, I think this is going to the shop.
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Decided to nut up and just DIY this job. Hopefully that doesn't turn out a mistake.
Found some wiring diagrams and it looks like the CRANK position sensor wiring in question runs under the intake.
So I went ahead and tried to remove the intake manifold. It hasn't gone well. Ran out of time as the day heated up but I got the thing basically loose but there is some other stuff somewhere holding it in back towards the firewall. Man I've always felt like the 4runner is a dream to work on, and it is for suspension, brakes, etc, but this is the stuff of nightmares. I'm historically a BMW guy and the way this engine bay is setup is worse than any BMW I've ever worked on.
I ended up breaking 2 more wiring harnesses just carefully trying to remove the intake. The wiring just came apart with no force at all.
I'm actually wondering if this car just needs an entirely new engine wiring harness. I'm seeing a minimum of four separate sub-harnesses that are going to be to be repaired, and it seems likely other wiring is in bad shape too. Has anyone done such a job and what does that entail?
Found some wiring diagrams and it looks like the CRANK position sensor wiring in question runs under the intake.
So I went ahead and tried to remove the intake manifold. It hasn't gone well. Ran out of time as the day heated up but I got the thing basically loose but there is some other stuff somewhere holding it in back towards the firewall. Man I've always felt like the 4runner is a dream to work on, and it is for suspension, brakes, etc, but this is the stuff of nightmares. I'm historically a BMW guy and the way this engine bay is setup is worse than any BMW I've ever worked on.
I ended up breaking 2 more wiring harnesses just carefully trying to remove the intake. The wiring just came apart with no force at all.
I'm actually wondering if this car just needs an entirely new engine wiring harness. I'm seeing a minimum of four separate sub-harnesses that are going to be to be repaired, and it seems likely other wiring is in bad shape too. Has anyone done such a job and what does that entail?
Okay, update.
Got the intake manifold completely off. I hate how they attach wiring harnesses to multiple separate parts.
Then after searching, studying, searching some more, I finally located the crank position sensor. It isn't where it's shown on the wiring diagram lol. It's actually under the engine whereas the diagram shows it as up-top. It's basically behind the AC compressor. Brutal to access. I probably could have avoided pulling the intake but it gave me a bit more room and since there are 2 broken harnesses and some rotted hoses up top it's worth refreshing.
Anyway, I managed to get the clip that holds the crank position sensor harness in place ahead of its termination off. barely. you have to do it completely by feel, pull up on the tab and then pull the clip back..where it bumps into something else and can't be removed. The trick is to basically manhandle it upwards a bit. Fun stuff.
As for the sensor connection itself, I have to remove the driver's wheel, serpentine belt, and AC compressor (yeah). I ended up using my SxS to drag the 4runner up hill from its parking spot and managed to push it into my workshop so I can do the job as this isn't happening on gravel.
Hopefully get that done tomorrow in the cool morning weather, and then redo the other connections. I think the wiring below the exhaust that is damaged is still making a connection so I'll find a way to cover it with new split-loom and pray. Then it's reinstalling the intake and figuring out all 900 connections on there.
Absolutely brutal job.
Got the intake manifold completely off. I hate how they attach wiring harnesses to multiple separate parts.
Then after searching, studying, searching some more, I finally located the crank position sensor. It isn't where it's shown on the wiring diagram lol. It's actually under the engine whereas the diagram shows it as up-top. It's basically behind the AC compressor. Brutal to access. I probably could have avoided pulling the intake but it gave me a bit more room and since there are 2 broken harnesses and some rotted hoses up top it's worth refreshing.
Anyway, I managed to get the clip that holds the crank position sensor harness in place ahead of its termination off. barely. you have to do it completely by feel, pull up on the tab and then pull the clip back..where it bumps into something else and can't be removed. The trick is to basically manhandle it upwards a bit. Fun stuff.
As for the sensor connection itself, I have to remove the driver's wheel, serpentine belt, and AC compressor (yeah). I ended up using my SxS to drag the 4runner up hill from its parking spot and managed to push it into my workshop so I can do the job as this isn't happening on gravel.
Hopefully get that done tomorrow in the cool morning weather, and then redo the other connections. I think the wiring below the exhaust that is damaged is still making a connection so I'll find a way to cover it with new split-loom and pray. Then it's reinstalling the intake and figuring out all 900 connections on there.
Absolutely brutal job.
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Spent two hours this morning working on the AC compressor bolts. There are four of them. I got one off.
The hardest of the four is giving me trouble. There is no angle to lay eyes on the bolt from behind, above, below, or the side. On top of that, there is no angle to get a tool to it.
I may end up having to remove the entire cooling system and driver's side suspension and brakes in their entirety. Possibly alternator as well.
This sucks.
The hardest of the four is giving me trouble. There is no angle to lay eyes on the bolt from behind, above, below, or the side. On top of that, there is no angle to get a tool to it.
I may end up having to remove the entire cooling system and driver's side suspension and brakes in their entirety. Possibly alternator as well.
This sucks.
I suspect crank sensors are known to be reliable and so toyota didn't put any engineering resources into accessing them.
That said, I really don't remember the engine bay being this crowded. I have a suspension lift which doesn't help, but dang. Like I can't even get the serpentine belt out because it won't fit between 2 of the pulleys, and I had to use a ratcheting breaker to get the tensioner even loose because a breaker bar just got jammed up against the battery with the belt off. I don't remember having these challenges last time I took all this stuff off.
Made the decision to just go ahead and pull the fan/shroud/alternator. Hopefully that helps with access. Now I just have to wait for the weather to cooperate. I have no AC in my shop and humidity is 99% here.
That said, I really don't remember the engine bay being this crowded. I have a suspension lift which doesn't help, but dang. Like I can't even get the serpentine belt out because it won't fit between 2 of the pulleys, and I had to use a ratcheting breaker to get the tensioner even loose because a breaker bar just got jammed up against the battery with the belt off. I don't remember having these challenges last time I took all this stuff off.
Made the decision to just go ahead and pull the fan/shroud/alternator. Hopefully that helps with access. Now I just have to wait for the weather to cooperate. I have no AC in my shop and humidity is 99% here.
