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Re: Mid/top-end loss and no "go" when mashing throttle - no codes
And no I did not pull fuel vacuum line to check for leaks. It takes very little to prime when turned on and holds pressure with car off for a long time. But I know that’s probably independent. I'll check.
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
So I pulled the vacuum line going to the FPR and found it to be completely dry, turned on key and no gas coming out. Also checked all eight injectors with ohm meter and found all between 16.2-16.4ohms. So that seems to be good. MAF and TPS connections/wires good.
In desperation I pulled the boot between the MAF and TB to see if I could see beyond the TB valves for a rag or something stuck in there by chance, and found the boot torn pretty bad, but it doesn't look like it until it is flexed. My guess is that under more airflow from the engine, the air filter/MAF is being partially bypassed and air is being sucked in through the crack (which probably flexes wide open under mid-high RPMs where I was having the most power loss) and would be my guess as to why the O2 reads lean - as only enough fuel is being put in for what comes through the MAF. I put some black silicone gasket maker and rubbed it into the cracks and stretched it in there, then cleaned it up. Will see how it does tomorrow. Otherwise, I'm at a loss as to what else could be wrong. Where could I get a new one, or are there aftermarket silicone hoses?
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Hmm, that information would have came in very handy earlier on had we known that, ya think lol? You know it's funny, when you mentioned that MAF code earlier on, I was almost tempted to tell you to disconnect the MAF sensor and try to run the engine on TPS/RPM only (Alpha-N, but not optimal) just to see if you had any power up top. Maybe I should have thrown that out there, but I think most of us initially thought you went through all of the external parts of the swap thoroughly as you were installing the replacement engine, but then again that boot can be easily overlooked. That has to be it because everything else has been covered. If you dare post back with the issue still in hand, then the next step will be to call an exorcist...
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Yeah you and me both, I had no idea and I pulled it off a few times during this whole thing. Well I take it for a spin soon.
I would still like to know why the o2 reading takes forever to get above zero every time engine is shut off and started even when warm. Shouldn’t it give a value right from the start if its heated and warmed up? But I’ll drive and log and see if it still does it.
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Kev, like I was saying in my last post, I wanted you to force Alpha-N by disconnecting the MAF sensor entirely. This will trigger the SES light of course, but it will also be forced to run on pre-configured fueling through the relationship between the TPS and RPM. The car will not run good at idle and part throttle, but this will at least let you know if the fueling issue up top is due to a skewed sensor, or an injector. If you have power this way, then it is either that tear in the boot being the issue, or back to the O2 being the issue. If you still don't have power this way, then it is back to the fuel itself being the issue, whether pressure related or injector related. Yes,I know you checked pressure and ohm checked the injectors, but there is nothing else at this point...
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Drove it with the fixed/repaired boot on, no change. Disconnected the MAF, fell flat on it's face, horribly. I then decided well screw it, let me check all the fuses. Pulled them out, none were blown, and plugged MAF back in. Car just about shoved my eyeballs out my ears and it was a new animal. Thought it was the MAF connection, but as I was driving home it got real jittery/jumpy/surging, like a switch was being flipped. Got back to the house, pulled the Inj 2/FP fuse, wouldn't start (of course). Pulled the Inj 1 fuse, back to loss of power but fairly smooth running (although not anywhere as good as with it plugged in, but I didn't have anything to compare it with), running like it had been. Put the fuse back in AND IT FELL OUT. Stupid female adapter had corroded way up in there in the fuse box where I couldn't see and it just fell apart. Spliced a new fuse holder into the Inj 1 bank, and boom, car is running like a champ now. Pulled the MAF connection again to see, and it ran way better than without left side injectors firing. Which would make sense as to why the single-wire O2 sensor wasn't working - cylinders were barely firing hot enough on that side to heat it up. My goodness, this thing is incredible. Ya'll ought to pull your Inj 1 fuses today and drive around in solidarity of what I had to go through the past few months of troubleshooting.
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Yeah, I'll log it this evening or sometime this week. Thanks for all your help guys, I appreciate it. Definitely one of the longest threads I've had, and what a pile of problems compounding the issue too.
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Got a MAF burnoff and MAF sensor high error. Here's the log for driving - freeway run. Over halfway in the log, I turned around and started from a stop on the onramp, uphill stretch for about 3/4 mile.
It did take a second to start this time which was usual as it normally fires right up. But I'll see how it goes in the morning (should be about freezing tonight). Also swapped out the heated Bosch 13077 O2 for the normal single-wire unheated Bosch O2 I had bought before the swap.
Re: Mid/top-end loss and no "go" when mashing throttle - no codes
Ok, now it’s taking about 4-5s of first start cranking before it fires up, then idles around 1000rpm. I shut it off and tried again, started pretty quick 1-2s. Will check back later today and see if it still takes a long crank to start.
05-01-2020, 10:09 PM
