How To Stop Pre-Detination Rattle?

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Here a quick check on the relay. If the vehicle continues to run then the relay is bad or the ground wire from ecu bad or ecu not giving a ground

Tryied to make a video


Thanks for the video!!!! Is the FPRelay all or nothing? Or can it work some & cause a lean issue? Thanks.
 
s***ty fuel.... More prevalent than everyone thinks.

Ethanolized fuel is wreaking havoc on EFI systems.

As is fuel mixed with water which we are seeing a lot of in the south.
 
****ty fuel.... More prevalent than everyone thinks.

Ethanolized fuel is wreaking havoc on EFI systems.

As is fuel mixed with water which we are seeing a lot of in the south.
No doubt about that! In my mower I've seen it turn to gel in as little as 3 weeks & turn to crystals in 6 months. Damn EPA sleeping w/corn farmers or something!!!! But if it was only s***ty fuel then a ton more 80 owners would be complaining.

I live in a relatively small town (<40K people) so I don't have the options of all the different fuel stations. Right now I'm trying Shell fuel but it seems to rattle as bad, or worse, than Valero & Murphy (Wal-Mart). I don't use Quick-Trip, RaceTrac or the other jumbo gas stations.
 
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Thanks for the video!!!! Is the FPRelay all or nothing? Or can it work some & cause a lean issue? Thanks.

The relay is not all or nothing. It has 2 modes of operation.
1 start and high load or acceleration
2 normal driving and idle

If yours runs with the resistor disconnected then there is a problem with the relay ( or less likely ground wire to ecu).
If the relays holding circuit is fried then you will be running the pump at max fuel psi which would cause the ecu to run the vehicle lean. In other words your fuel psi should be lower under most all conditions and that's what the ecu thinks- when your o2 sensor tells the ecu that there is to much fuel ( because of higher fuel psi) the ecu will shorten the duration of the injector causing a lean condition.
If this is good you may want to check the return line from your fuel psi regulator also to make sure it is not kinked or blocked. Just disconnect it and make sure you can blow thru it but take your gas cap off two. GL
 
The relay is not all or nothing. It has 2 modes of operation.
1 start and high load or acceleration
2 normal driving and idle

If yours runs with the resistor disconnected then there is a problem with the relay ( or less likely ground wire to ecu).
If the relays holding circuit is fried then you will be running the pump at max fuel psi which would cause the ecu to run the vehicle lean. In other words your fuel psi should be lower under most all conditions and that's what the ecu thinks- when your o2 sensor tells the ecu that there is to much fuel ( because of higher fuel psi) the ecu will shorten the duration of the injector causing a lean condition.
If this is good you may want to check the return line from your fuel psi regulator also to make sure it is not kinked or blocked. Just disconnect it and make sure you can blow thru it but take your gas cap off two. GL
Mine cut off after about 2 seconds just like yours did. I noticed on my way to work watching my UltraGauge that when it starts to rattle the knock sensor doesn't lower the timing. It'll be pinging and the timing will be up to 23* to 25* advanced. The knock sensor should lower (retard) the timing low enough for it to stop pinging and should do it quickly. I can hold throttle steady for eternity with it pinging and timing doesn't drop. I believe there's 2 knock sensors in the 1FE??? Shouldn't it throw a code(s) if the knock sensor is faulty?
 
Mine does exactly the same thing. No codes, I am told a bad knock sensor will throw a code. I just changed my plugs to a lower temp yesterday, need to do some test driving today to see what the results are. All vacuum lines appear to be good and going in the right direction.

I also have included pics of the oil fouled plugs. They had about 15k miles on them. Too me it looks like carbon build up is excessive and needs to be addressed. I have seafoamed this twice, will need to use another product...

LC SPlug 010.webp
LC SPlug 003.webp
LC SPlug 002.webp
 
Your plugs look the opposite of mine. Mine are charred white. I just read a different thread where the guys rig was pinging and what fixed it was the distributor was off 1 tooth. No matter how much he retarded the timing it wasn't enough. I replaced my dizzy o-ring this past winter. I wonder if I got it one tooth off and it's only showing because of the heat? Have you removed your dizzy since last summer? How do I determine the dizzy isn't one tooth off?
 
I did but it was pinging then too. Wouldn't being off a gear show timing way off???
 
I did but it was pinging then too. Wouldn't being off a gear show timing way off???
I'd imagine it'd be waaaaay off. My UG is showing mine at +6* to 7* at idle. I'm guessing that's not my problem. Looks like my focus may be knock sensor?
 
If your plugs are charred white you're running lean....
That's what I'd normally think. But why and is it only a lean condition causing the pinging?
 
What numbers should I be seeing on my short and long fuel trims via UltraGauge to know for a fact if I'm running lean?
My short trim , at idle, stays between +.78 and +3.91 but fluctuates between -3.5 and +4.9 at 1,800rpm. My long trim at idle is -4.7 steady but increases up to 0.00 when I idle up to 1,800rpm.

It appears these numbers are completely acceptable and show its not running lean, correct?
 
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I'd imagine it'd be waaaaay off. My UG is showing mine at +6* to 7* at idle. I'm guessing that's not my problem. Looks like my focus may be knock sensor?

Whats your timing when you jump it and check it with a time light?
 
Can't trust your STFT and LTFT if your O2 sensors are bad. I trust the look of the plugs more than the O2's.

What numbers should I be seeing on my short and long fuel trims via UltraGauge to know for a fact if I'm running lean?
My short trim , at idle, stays between +.78 and +3.91 but fluctuates between -3.5 and +4.9 at 1,800rpm. My long trim at idle is -4.7 steady but increases up to 0.00 when I idle up to 1,800rpm.

It appears these numbers are completely acceptable and show its not running lean, correct?
 
Whats your timing when you jump it and check it with a time light?
Between 6 and 7*. That's my estimate of it between 3 and 10* on the timing plate.
 
Can't trust your STFT and LTFT if your O2 sensors are bad. I trust the look of the plugs more than the O2's.
O2 sensors are brand new, <1 week old. Made zero difference.
 

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