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I have a slight miss, not sure if that is why or what is causing the problem. Replaced my fuel pump a few years ago but I think it may be going out since it has making a weird noise the last week or so, although I'm sure that is not the idle miss problem.
Last edited by Mishawaka; Nov 11, 2017 at 07:24 PM.
Have you checked the pump? First thing I would do is see if it gets to pressure. Plug the gauge in and turn it on to run position. It should cycle up and let's see what the pressure gets to. See if it holds. If that is good, I would tape it to the windshield and do a WOT run to see what it does under load.
Not that you cannot change the pump seeing how old it is but you should do the test first.
You might have to change the FPR if it is bad. Pull out the hose going to the manifold and take a sniff. You see or smell gas and we know the FPR diaphragm is not intact.
I changed the fuel pump and FPR within the last few years. Pressure is OK but leakdown is probably quicker than it should be. I am having intermittent fuel pump issues and looking to get a new one as I mentioned in my other thread, just need to choose one. The pump has been making a strange noise at startup lately.
Last edited by Mishawaka; Nov 12, 2017 at 12:17 AM.
Forgot to mention, sometimes at startup it has pretty low idle. Sometimes I shut it down and then it idles fine after the second start. I replaced the relay already. I would post the actual log file but don't see how I can do it on here.
I changed the fuel pump and FPR within the last few years. Pressure is OK but leakdown is probably quicker than it should be. I am having intermittent fuel pump issues and looking to get a new one as I mentioned in my other thread, just need to choose one. The pump has been making a strange noise at startup lately.
Where is the leakdown at? What I would do is crimp off the return line and pressurize it and see what happens. If it doesn't leak, it is likely the FPR. If it still leaks, repeat test but crimp off the feed line. IF it holds, the leak is between the crimp and the pickup.
What did you change the pump with? Did you remove the pulsator?
A few years ago, but ended up putting the stock ones back in because of a long start problem. I ordered 24s, they sent me 22s by accident and then sent me the 24s. both had long start problems. My stock ones start with no hesitation so I decided to reinstall them and haven't had a long start since. But I still they need to be replaced. Unfortunately, Im not sure if I should go with the previous supplier and have them exchanged for 22s or go with someone else. I bought them from a supplier on here, when I discussed it here the supplier and another member got into a big argument so I dont want to mention.
Last edited by Mishawaka; Nov 12, 2017 at 12:43 AM.
Forgot to mention, sometimes at startup it has pretty low idle. Sometimes I shut it down and then it idles fine after the second start. I replaced the relay already. I would post the actual log file but don't see how I can do it on here.
I don't see a low idle. Look at your "Desired Idle" and "Idle Speed". It wants 650 rpm and you are at 775 rpm.
A few years ago, but ended up putting the stock ones back in because of a long start problem. I ordered 24s, they sent me 22s by accident and then sent me the 24s. both had long start problems. My stock ones start with no hesitation so I decided to reinstall them and haven't had a long start since. But I still they need to be replaced. Unfortunately, Im not sure if I should go with the previous supplier and have them exchanged for 22s or go with someone else. I bought them from a supplier on here, when I discussed it here the supplier and another member got into a big argument so I dont want to mention.
Not sure what those specs are but you can ask him. That seems to be unlisted, spec wise. Is that your previous supplier? You can give RC Engineering a call and see if they have stock spec ones. I have used them before for other projects. Witchunter I have heard of but never personally used.
I don't see a low idle. Look at your "Desired Idle" and "Idle Speed". It wants 650 rpm and you are at 775 rpm.
I was driving it at the time, once I start driving it the idle is fine. Sometimes after I shut it down then restart in a bit it idles low again but after driving a bit it will idle fine with no problem. It only happens at start up, whether the engine be cold or warm. Here is an idle capture when it started fine and engine warmed. Still has the slight misfire though. I will try to make a video of the file.
Lets try this. With the engine at stable operating temp, everything but the motor off and idling, what is the IAC position, give or take a few? It should be around 20-30 counts. It can fluctuate but not fall off to 0.
This one is toward the end of the log after warmed up and idle. It was a little cool that day so I may have had the heater on, I don't recall. The IAC readings pretty much stayed at those readings about that time during the play back.
One snap shot is almost useless. You need to do some graphing with fuel O2 and IAC values all in the same graph to see if readings are similar but out of phase. I am betting there is a vacuum leak somewhere with IAC so low.
One snap shot is almost useless. You need to do some graphing with fuel O2 and IAC values all in the same graph to see if readings are similar but out of phase. I am betting there is a vacuum leak somewhere with IAC so low.
Yeah I feel someone needs the actual file to see whats going on. I checked for vacuum leaks awhile back, the only thing that was suspect was the line from the brake pedal to the cruise control, I replaced that and the other line on the cruise control. I sprayed everything down with carb cleaner and idle didn't change once.
I have replaced the AIC, AIT, TPS(which had a flat spot when tested), EGR, PCV, fuel filter, pulsator, fuel pump. I think that's is, that is related anyways. I deleted the air injection but this problem has been there before I did that.
