Engine dead after tune-up!?
#1
This happened to a 1991 4runner V6 4x4. I installed some spark plugs and wires today. In the process, I had to remove the entire intake up to the throttle body to gain access to the spark plugs. Unfortunately, the tubing was baked (hard and not very flexible). I successfully disconnected part of the intake, but the hose running from the silencer the the throttle body tore in the process of removal. I decided to proceed with the work; I completed a while later. I tried firing up the car without the intake and plugging all the vacuum hoses up, but the engine would start up for a second or two, and just die. I went back to the auto shop to confirm these were the right plugs, and even tested each plug wire with the old wires. Could the intake not being connected be what is causing the engine to die?




#2
if the throttle body is not securely, and without leaks, connected to the air flow meter (on top of the filter) the engine will not run for more than a few seconds. The air flow meter keeps the fuel pump running once the engine starts. If it's not hooked up, the engine will die.
#3
I was thinking that it had to have the connection of those two (the intake filter housing, due to the vaf, and the throttle body) to run, but wasn't sure.
Last edited by Texas91Runner; Mar 22, 2009 at 09:02 PM.
#4
not sure what that meant...
if you were thinking it had to have an airtight seal, why didn't you check?... 'cause it should.
So, back to the start:
you ask "Could the intake not being connected be what is causing the engine to die?"
I answer "Yes, that could be the problem, and based on what you wrote, seems to be THE problem."
if you were thinking it had to have an airtight seal, why didn't you check?... 'cause it should. So, back to the start:
you ask "Could the intake not being connected be what is causing the engine to die?"
I answer "Yes, that could be the problem, and based on what you wrote, seems to be THE problem."
#5
I wasn't really concentrating when I posted that last one. I edited it though. 
Yeah, that makes more sense now. I have to wait until Tuesday for the hose to get in, and I'll give it a try. That small second portion cost $50!

Yeah, that makes more sense now. I have to wait until Tuesday for the hose to get in, and I'll give it a try. That small second portion cost $50!
#6
If the air going into the engine doesn't pass through the AFM (on top of the filter) the AFM will not open enough to keep the fuel pump running.
May not make sense but it's true. The AFM isn't only there to measure how much air goes into the engine for air/fuel mixture issues. It's also used by the system to keep the fuel pump running once the engine starts.
It does 3 things: measures how much air goes into the engine, measures the temperature of that air, and if the airflow is above a certain level, grounds the relay (a.k.a. Circuit Opening Relay) that turns the fuel pump on.
So no air through the AFM means the COR (Circuit Opening Relay) turns off when you let go of the key after starting the engine and the fuel pump stops working and the engine dies within a few seconds afterwards.
May not make sense but it's true. The AFM isn't only there to measure how much air goes into the engine for air/fuel mixture issues. It's also used by the system to keep the fuel pump running once the engine starts.
It does 3 things: measures how much air goes into the engine, measures the temperature of that air, and if the airflow is above a certain level, grounds the relay (a.k.a. Circuit Opening Relay) that turns the fuel pump on.
So no air through the AFM means the COR (Circuit Opening Relay) turns off when you let go of the key after starting the engine and the fuel pump stops working and the engine dies within a few seconds afterwards.
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#8
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From: NW Ark on wooded ten acres...Ozarks at large!
Duck tape will work in a pinch......depending on how bad it ripped. Use narrow strips as opposed to the full width. That way it wraps around better/more securely without kinking up. I've done this successfully. Lasted a good while, too.
#9
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From: maple ridge, British Columbia, Canada
#10
#11
The hose was a gonner.. It ripped in two complete pieces right at the bend: one which surrounded the throttle intake, and the remainder.
#12
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From: NW Ark on wooded ten acres...Ozarks at large!
Search "ISR mod".
#14
Depends on how you do it, what you use, and the resulting bend in the intake tube. I used electrical conduit with a 45* bend. It doesn't afford much room for reaching plugs or even the dipsticks, but it was inexpensive and works well, so there......hehehe.
Search "ISR mod".
Search "ISR mod".

After I complete my sound system, I'll look into putting some money there.
#15
#19
Um....I had a 95 toyota 4runner and did not have to remove intake to get to plugs... you gotta know what your doin and save that kinda hastle. Unless your hands are ing monsters you should have been able to do it with out removing intake. so u ed up


