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haha help me if u can, tryed everyone else

1685 Views 48 Replies 8 Participants Last post by  cannodal19
hey guys whats goin on, just bought a 91 eagle talon off my brother that he's been working since forever, well he told me it needed a turbo ecu, that the one he had in there was a non-turbo one, so I got one for free off a 91 eclipse, found out that the ecu was a 90 though, so I did some research and found out that u have to replaced two wires, so I did that, still hada problem, then I went off ebay and bought another one, and the problem i'm having is, when I pressed the gas peddle, the rpms go down, when I let off, the rpms go up, then if I get the rpms up past 4 grand, then the peddle acts normal and i can rev it, and sounds awsome, but once the rpms go back past 3 thousand then the gas goes right back to normal, I've check the ecu, and no leaks, I have a code, and for some reason I can't get the light to come on, like ya know how u check your self, so I look around, and either the coil pack, or the throttle position sensor, so I changed both of them, still the same damn problem, help me if u can, lol cause no one else hasa fucking clue, I've also look at vfaq.com didn't have anything on there, and looked at every possible forum, I'm about to give up.... :( Ps I'm new on this site
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Are you sure you did the wiring job correctly? Have you tried a 91 ECU? There were quite a few difference in the motor set up on the 90's vs the 91's.
The wiring harness is back to normal, and the 91 ecu is installed, with the other ecu it won't rev past 4 like the 91 does, I need to figure out how to check the check engine light, that should tell me, and I foudn the forums for that, but couldn't figure it out
Maybe the ISC motor
I have seen and fixed this exact problem before. It was a misadjusted TPS problem on my gf's car. It did that very thing making driving the car home from the guy she bought it from a PITA. Set the TPS as per the manual and it all cleared up.
set it as the manual?? like the manual book?? I took out the thottle positioning sensor, and replaced it, and still no good
so how do u adjusted the tsp, I didn't see anything to adjust on it
I don't have voltage values in front of me but it is all laid out in the shop manual. Chiltons, Haynes, or factory.

Are you using larger injectors and something to tune them? Out of curiousity.
go to www.vfaq.com and it tells you how to adjust the ISC. You should be able to loosen the 2 bolts holding it onto the throttle body and movie it to either side and hook an ohm meter to 2 of the connectors (i forget, check vfaq) and it should be a certain value.
laxdudeee said:
go to www.vfaq.com and it tells you how to adjust the ISC. You should be able to loosen the 2 bolts holding it onto the throttle body and movie it to either side and hook an ohm meter to 2 of the connectors (i forget, check vfaq) and it should be a certain value.
It's not the isc i believe. This is the site you need: www.plymouthlaser.com/tps.htm
MegaGS said:
It's not the isc i believe. This is the site you need: www.plymouthlaser.com/tps.htm
meant TPS my bad, mind going to fast
Have you checked for boost leaks?
maybe catalytic converter?, posible maf sensor, also need to more about your set-up, like mods and such, with out knowing that no-one here will be able to help much
Ok heres mods, fully ported race head, 5 angle vavle job, compression raised to 10:0:1, manuel boost gauge, the hole engine has been rebuilt, with mostly oem parts, my brother has been working on it since 00.. Fully custom 3" ex, straight pipe, I have a ported, clipped, and 34mm flapper Big 16G coming, 255 fuel pump coming also, no as for a boost leak, I'm sure I don't because after u get it up to around 4 grand and the car acts normal, the boost gauge read up to ten, Thats where we have to boost set, cause I have stock injectors at the moment, I have 750cc injecs for the car, but waiting for fuel pump
that high of compression is a lil high, my bet is on tuning issues, you got a logger?, if not you need 1, if not that, then a dyno, everything else is going to be shots in the dark, timing could be getting skewwed, could be kitting fuel cut, but with out a logger, you will prob never know
If you are sure everything is right w/the ECU, I would check the timing. Head was taken off, but was timing set correctly? You adjust the tps by loosening the 2 bolts and have a scanner(in my case) and move around the tps till its within range and tighten, but dont tighten it too much. Also, when you tighten it normal it the voltage will change, so you have to fiddle with it for a good time. Hopefully that helps.
I'm going to play with the tps, I don't have a voltage meter at the moment, so I'll just keep playing with that, i'm also going to check the fuel filter to see if thats clogs, the timming is right, I know that, the ecu was rebuilt and we checked it in a nother running tsi that my friend has and that worked, I'm going to also try to learn how to check for boost leaks, and to check the engine light, thanks, I'll give u guys more updates tomorrow after I spend all day working in the cold on problem child..
OH yeah, one more thing, I know that high compression u can't run really high boost on a stock bottem end, so whats the max's, my brother told me 18, but thats with a stock 1gen, without the compressions raised, all I know my brother told me that when the top end was done, some how it raised the compression to that, so I have no clue where to set the boost, at the moment its at 10, and I'm going to lower it to 8 for now intill I get the proper tools to tune it
Why was compression raised? for what purpose? are the 750cc's installed? And make your 'problem' more clear, its a little hard to understand and decipher.
Ok, I'm not sure if the compression is raised, my brother told me it was, but the only way that I know u can raise it is by different pistons, so I'll find out more on that issue.. And the 750cc injectors are not installed, I need the fuel pump first then I can install them.. and as for the problem, when ever I hit the gas, it starts to die, then when I let off of the gas its gets fuel and the rpms goes up.,, so If I pump the gas peddle really fast I can keep the engine reved, but everytime I hit the gas, it doesn't rev like its soposted to, it dies, then when u let up on the gas peddle it revs up.. its weird.. I'm going to try to readjusted the TSP and then check the fuel filter to make sure its not cloged.. then I'm going to see what the check engine light is telling me, probley a sensor but I will find out after work
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