[Shxtbox240]

Ok so when this first happened I was driving home and the throttle felt very snappy when barely pressing the throttle. As I noticed this random thing happening it randomly backfired like crazy and started jurking very hard on steady throttle. Holding the gas on idle steady would sound line a rotary. From the point on I have been working on this situation and replaced these listed below

• coolant temp sensor
• put a higher octane in, running 91 now
• Brand new fuel filter
• cleaned the maf
• new spark plugs
• recently did new fuel injectors a month before this problem
• New 02 sensor in exhaust manifold

Here is a link from when I did these (instagram)

@240sx.vic on Instagram: "Pls read: changed coolant temp sensor, cleaned maf, put higher octane gas and changed filter and now the car idles perfect, but giving it gas makes it cut out and bog. When the car is cold it doesn't want to idle but giving it gas is instant and won't cut out or bog when revving. Anyone have any ideas? Maybe throttle position sensor or vacuum leak?"

@240sx.vic shared a post on Instagram: "Pls read: changed coolant temp sensor, cleaned maf, put higher octane gas and changed filter and now the car idles perfect, but giving it gas makes it cut out and bog. When the car is cold it doesn't want to idle but giving it gas is instant and won't cut...

www.instagram.com

When I did those things at the time the car did not want to Idle on cold but it would rev instantly and then when it warmed up it would idle but the rotary sounding acceleration would happen again so I replaced these

• new fuel pump
• new fuel pressure regulator
• new throttle position sensor
• I replace a hose from the intake that goes downwards, it had a cut in it and lost coolant and then I found a possible hose connection from the back of the intake into some lime faceing the back of the fire wall that I saw on youtube cause i couldnt find where it would go anywhere.

Here's the link when I did these parts after (Instagram)

@240sx.vic on Instagram: "Update: changed fuel pump, pressure regulator, found where a unknown vacuum hose goes to, replaced coolant hose that was ripped that goes into the intake manifold, replace throttle position sensor and it's running ok-ish, Still running rich though even though I changed coolant temp sensor and it wasn't but now it is. However it's misfiring, so maybe the maf is bad. I did clean it and it did nothing"

@240sx.vic shared a post on Instagram: "Update: changed fuel pump, pressure regulator, found where a unknown vacuum hose goes to, replaced coolant hose that was ripped that goes into the intake manifold, replace throttle position sensor and it's running ok-ish, Still running rich though even...

www.instagram.com

After doing those the car idles and won't die when it's cold. The throttle response is faster but it's still doing the weird rotary sound when you are steady on the throttle.

I have 4 parts on the way, a new distributor, a new maf sensor cause my maf in it rn is some cheap ebay crap, a new ignition coil and some new spark plug wires.
so I'll update what happens when I install those, but In the mean time If anyone has any ideas of what it might be I would love help cause I have no cars to get to work rn I'm borrowing co workers crap lol.

I would also like to say It ran perfect up until this and I had recently done a head gasket and did the intake manifold gasket and aac gasket and with that like I said new fuel injectors

 

[Shxtbox240]

Update: changed fuel Injectors, spark plugs, spark plug wires and ignition coil runs a tiny bit better. Unplugged every spark plug wire individually and each time I unplug one it does affect idle and make it worse so nothing stays the same. So that means fuel is good?

It still does the weird thing when giving acceleration it sounds like a rotary idling

Waiting for my new distributor to come and my maf to come still.... will update once I get those

@240sx.vic on Instagram: "This time I did injectors, spark plugs, spark plug wires, ignition coil. Still have a distributor and maf coming... hopefully that'll fix this crap"

@240sx.vic shared a post on Instagram: "This time I did injectors, spark plugs, spark plug wires, ignition coil. Still have a distributor and maf coming... hopefully that'll fix this crap". Follow their account to see 75 posts.

www.instagram.com

 

[Valley_grps_707]

Fuel is good enough to make it run. Double check that coolant line is properly routed to where it should go and isnt spewing coolant into the manifold, if it is you will see coolant puddled on the bottom of the manifold when you open the throttle body. Check the resistance of the injectors, and if that checks out check compression. You can borrow a compression test kit at an auto parts store just call in advance to make sure they have it.
For specifcations search on here, google or look for the factory service manual (fsm). It will also have routing diagrams.

 

[laurenheitz0]

This reminds me of my 240 that had a lot of issues never really figured it out but it was missing a wire on the maf sensor because it was supposed to have three wires but mine only had two and it was the signal wire that was missing so I added one from the tps sensors signal wire and it helped a good bit do give update when you fix it!

 

[Shxtbox240]

Update: I replaced spark plug wires, ignition coil, gapped new spark plugs to .46, set idle sensor to 0.5 on 200 ohms and put a brand new maf in, it's pretty much fixed from what I can tell however the idle it's self is very high. I don't have a working tach but from sound it's pretty high.

Tomorrow I'm gonna mess with the idle some more by adjusting the throttle body blade with the screw. And unplugging the tps and adjusting the screw at the back of the intake on the aac.

I did buy a new distributor but that shi don't fit lmao so I'll just get a new cap and rotor cause the rotor is wrong on the new one but whatever.
I'll post another vid tomorrow but I can say it's pretty much fixed from what I can tell

 

[Shxtbox240]

Leaving work today it was normal everything was going well and then had to get gas. So I pulled in and noticed when I went in 1st gear in low rpms It would be a easily noticeable misfire. Was able to drive home but otw closet to home it ended up getting worse. Luckily it's not as bad as the first misfire that was stated at the beginning of the thread where it would bog really bad this one is only noticeable in lower rpm but higher rpm it goes away

 

[Shxtbox240]

Leaving work today it was normal everything was going well and then had to get gas. So I pulled in and noticed when I went in 1st gear in low rpms It would be a easily noticeable misfire. Was able to drive home but otw closet to home it ended up getting worse. Luckily it's not as bad as the first misfire that was stated at the beginning of the thread where it would bog really bad this one is only noticeable in lower rpm but higher rpm it goes away

Day after this post I fixed it by swapping in New plugs and gapped to .47