5MGE acceleration problems

drs77 · 11-05-2006, 08:44 PM

Okay, first off I have to explain. I don't own a Supra, I own a 4Runner with a (technically 84 Cressida) engine, but after visiting many places, including Supracharged, I haven't solved my probem. It seems that this site has the most knowledgeable people with these types of engines so here I am. Basically my truck starts good, idles good, revs good (in N). The problem is when I let out the clutch and go, it goes like crap. It sounds like air is billowing out the exhaust and it hardly wants to go up a hill. On a flat spot it accelerates a little better (still crap, I'm talking like 15mph in 5secs), but when it hits a certain RPM threshold, maybe 2500-3k rpm (don't know what it is, no tach), it takes off like a bat out of hell. I did all the usual tests and din't find anything weird. Since this eng is swapped out, I figured there might be some wiring issues. The only thing that I can think of is the fact that I didn't hook up the speed sensor. The reason being is that it is an A/T ecu, and the speed sensor wire goes to a box with about 10 other wires coming out of it that I believe go to the ECT box, which I don't need since I have a manual. Well, anywho, it's driving me crazy and if I can get some help I'd greatly appreciate it. Also, if anybody out there is planning on doing this swap, let me know so I can tell you some of the issues that I've had to deal with to make it work with a SAS, hi-steer, 3 core w/dual fans, and hood closing with no body lift....Peace...

Dyl

mrnickleye · 11-05-2006, 11:42 PM

Has the truck ever run good with this engine??
Or did you just do the swap??

drs77 · 11-06-2006, 12:04 AM

Ijust did the swap, turned it over for the first time a few days ago. That's kinda an issue since this a hybrid so to speak, nothing is straighforward. One thing that was interesting. The first time I turned it over, it idled very high. When I put it in gear with the high idle, it ran good, just really high idle. Then I realized that I didn't connect the ISC or the VSV. Hooked those up and it brought the idle to normal. Cheked the resistance of the ISC, all was good, didn't check the VSV, but assumed was good (same circuit). One other thing to note. When I was first manually operating the lingake, I heard a moderately loud pop that sounded like it was coming from the EGR area, almost as if something broke loose, but not necessarily in a bad way, but maybe, not sure. Well, out to the garage.....again...

Dyl

drs77 · 11-06-2006, 11:41 PM

Here's one thing that I've found. When accelerating, if I mash the throtle, or even slighty rapidly press the pedal is when it starts to bog down. If I very slowly and gently press the pedal at a constant rate it seems to accelerate normaly for that speed, but that is still super slow....Anybody?

11-05-2006, 08:44 PM	#1
drs77 Stock Join Date: Nov 2006 Location: Rogue Valley Posts: 4	5MGE acceleration problems Okay, first off I have to explain. I don't own a Supra, I own a 4Runner with a (technically 84 Cressida) engine, but after visiting many places, including Supracharged, I haven't solved my probem. It seems that this site has the most knowledgeable people with these types of engines so here I am. Basically my truck starts good, idles good, revs good (in N). The problem is when I let out the clutch and go, it goes like crap. It sounds like air is billowing out the exhaust and it hardly wants to go up a hill. On a flat spot it accelerates a little better (still crap, I'm talking like 15mph in 5secs), but when it hits a certain RPM threshold, maybe 2500-3k rpm (don't know what it is, no tach), it takes off like a bat out of hell. I did all the usual tests and din't find anything weird. Since this eng is swapped out, I figured there might be some wiring issues. The only thing that I can think of is the fact that I didn't hook up the speed sensor. The reason being is that it is an A/T ecu, and the speed sensor wire goes to a box with about 10 other wires coming out of it that I believe go to the ECT box, which I don't need since I have a manual. Well, anywho, it's driving me crazy and if I can get some help I'd greatly appreciate it. Also, if anybody out there is planning on doing this swap, let me know so I can tell you some of the issues that I've had to deal with to make it work with a SAS, hi-steer, 3 core w/dual fans, and hood closing with no body lift....Peace... Dyl

11-05-2006, 11:42 PM	#2
mrnickleye 1000whp postwhore Join Date: Jun 2005 Location: Mojave Desert, Calif. Posts: 1,705	Has the truck ever run good with this engine?? Or did you just do the swap?? __________________ Had a Red 1989 N/A. Automatic. Sports Pkg. w/wing. TEMS, and some nice MODS. Sold to a friend 10/08/08.

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11-06-2006, 12:04 AM	#3
drs77 Stock Join Date: Nov 2006 Location: Rogue Valley Posts: 4	Ijust did the swap, turned it over for the first time a few days ago. That's kinda an issue since this a hybrid so to speak, nothing is straighforward. One thing that was interesting. The first time I turned it over, it idled very high. When I put it in gear with the high idle, it ran good, just really high idle. Then I realized that I didn't connect the ISC or the VSV. Hooked those up and it brought the idle to normal. Cheked the resistance of the ISC, all was good, didn't check the VSV, but assumed was good (same circuit). One other thing to note. When I was first manually operating the lingake, I heard a moderately loud pop that sounded like it was coming from the EGR area, almost as if something broke loose, but not necessarily in a bad way, but maybe, not sure. Well, out to the garage.....again... Dyl

11-06-2006, 11:41 PM	#4
drs77 Stock Join Date: Nov 2006 Location: Rogue Valley Posts: 4	Here's one thing that I've found. When accelerating, if I mash the throtle, or even slighty rapidly press the pedal is when it starts to bog down. If I very slowly and gently press the pedal at a constant rate it seems to accelerate normaly for that speed, but that is still super slow....Anybody?