need help troubleshooting bad running engine

[hangontight]

My 1987 GN has been sitting for a while, and really not driven a whole lot in the last ten years, other than around the block for short rides. I was hoping to get her cleaned up and start driving more often, it was my daily driver years ago. the car has some nice upgrades and has always ran great. The last couple times I have taken it around the block the VDO coolant temp gauge would quickly spike from 180 to over 200 then drop down to 180 again, ( I have a GNX style dash made by AVC) the car showed no signs of overheating and was running good so I thought it may be a bad sensor or maybe the thermostat was sticking. I put in a new 160 degree thermostat and new stainless housing & a brand new radiator cap, took it around the block & the temp gauge did the same thing, then to make matters worse the car lost power then ran ruff I was right in front of my house when this happened so just coasted into the driveway. I opened the hood and realized the upper hose clamp on the uppipe was not tightened all the way and it blew off.(duh) I put it back on then took it around the block again, it ran fine then I got on the gas, got it up to about 15 lbs of boost, let of the gas then it ran like crap again, so I thought the hose may have blown off again, opened up the hood & everything is tight and the connecters seems to be tight, don't see any vacuum leaks. the cars idles rough & is running bad. I hope its not a head gasket? the oil is clean, no engine trouble light came on. I don't have a scan master. On a side note I had planned on flushing the coolant or even possibly getting a new radiator and also getting a Turbo Tweak Chip mine is an old school Modern Muscle chip programed for 36lb Bosch Blue tops. Any ideas on what may have happened to have the car start running bad?

 

[mikestertwo]

What MAF do you have on the car?

 

[hangontight]

What MAF do you have on the car?

stock - AC Delco

 

[Tom87GNX]

Could be a MAF issue. How old is the gas in the tank? Stale gas is not good for any car especially a turbo car. Spring cleaning should always be done on our cars and it's even more critical when they have sat for extended periods. In a lot of cases leaving a car sit for long periods of time is equal to or sometimes worse than driving it regularly.


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[hangontight]

What MAF do you have on the car?

stock - AC Delco

Could be a MAF issue. How old is the gas in the tank? Stale gas is not good for any car especially a turbo car. Spring cleaning should always be done on our cars and it's even more critical when they have sat for extended periods. In a lot of cases leaving a car sit for long periods of time is equal to or sometimes worse than driving it regularly.


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Been keeping the tank fairly low, and adding fresh gas now & then when taking it out (non-ethanol) I have a new fuel filter I will put on. I have an older MAF translator & LS1 sensor that I tried years ago when they 1st came out for the Buicks, I did not like the way it ran so I bought a new stock one, but I guess I could try it incase the MAF just took a dump. The car felt like it did when the hose 1st came of the throttle body but everything is on tight now?

 

[hangontight]

stock - AC Delco

Been keeping the tank fairly low, and adding fresh gas now & then when taking it out (non-ethanol) I have a new fuel filter I will put on. I have an older MAF translator & LS1 sensor that I tried years ago when they 1st came out for the Buicks, I did not like the way it ran so I bought a new stock one, but I guess I could try it incase the MAF just took a dump. The car felt like it did when the hose 1st came of the throttle body but everything is on tight now?

Found my older LS1 MAF 3" sensor & MAF Translator plus(version 4.0). I wanted to install to see if the MAF sensor is bad, but before I do this I have some questions. As of now I can not find the original install instructions but I do remember I had to splice into the wiring up towards the firewall behind the coil pack, I hated to do this but at the time at had to. Looking at the newer version 6.25 the picture shows less wires coming out of the translator & looks like there is a "Plug & Play Adaptor" so no need to splice. Is my older version worth using? is there an adaptor for it? what is the difference between ver 4.0 & 6.25 see attached pictures.

View attachment 286041

 

[Tom87GNX]

I run an LT1 MAF and 6.25 translator, made a hell of a difference in throttle response and overall drivability


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[Tom87GNX]

For simplicity I would recommend the standard MAF translator, the plus add the ability to advance or retard timing which could be difficult to tune for some. Also if that's the MAF your using its an LT1 MAF and its plug and play with the 6.25 MAF translator- no adapter needed


Sent from my iPhone using Tapatalk

 

[hangontight]

stock - AC Delco

Been keeping the tank fairly low, and adding fresh gas now & then when taking it out (non-ethanol) I have a new fuel filter I will put on. I have an older MAF translator & LS1 sensor that I tried years ago when they 1st came out for the Buicks, I did not like the way it ran so I bought a new stock one, but I guess I could try it incase the MAF just took a dump. The car felt like it did when the hose 1st came of the throttle body but everything is on tight now?

Found my older LS1 MAF 3" sensor & MAF Translator plus(version 4.0). I wanted to install to see if the MAF sensor is bad, but before I do this I have some questions. As of now I can not find the original install instructions but I do remember I had to splice into the wiring up towards the firewall behind the coil pack, I hated to do this but at the time at had to. Looking at the newer version 6.25 the picture shows less wires coming out of the translator & looks like there is a "Plug & Play Adaptor" so no need to splice. Is my older version worth using? is there an adaptor for it? what is the difference between ver 4.0 & 6.25 see attached pictures.

View attachment 286041 View attachment 286044 View attachment 286045 View attachment 286046

 

[hangontight]

stock - AC Delco

Been keeping the tank fairly low, and adding fresh gas now & then when taking it out (non-ethanol) I have a new fuel filter I will put on. I have an older MAF translator & LS1 sensor that I tried years ago when they 1st came out for the Buicks, I did not like the way it ran so I bought a new stock one, but I guess I could try it incase the MAF just took a dump. The car felt like it did when the hose 1st came of the throttle body but everything is on tight now?

Found my older LS1 MAF 3" sensor & MAF Translator plus(version 4.0). I wanted to install to see if the MAF sensor is bad, but before I do this I have some questions. As of now I can not find the original install instructions but I do remember I had to splice into the wiring up towards the firewall behind the coil pack, I hated to do this but at the time at had to. Looking at the newer version 6.25 the picture shows less wires coming out of the translator & looks like there is a "Plug & Play Adaptor" so no need to splice. Is my older version worth using? is there an adaptor for it? what is the difference between ver 4.0 & 6.25 see attached pictures.

View attachment 286041 View attachment 286044 View attachment 286045 View attachment 286046

For simplicity I would recommend the standard MAF translator, the plus add the ability to advance or retard timing which could be difficult to tune for some. Also if that's the MAF your using its an LT1 MAF and its plug and play with the 6.25 MAF translator- no adapter needed


Sent from my iPhone using Tapatalk

Ok to be be clear the MAF in the picture is an LT1 and I would be better off buying a new 6.25 version MAF sensor no wire splicing needed?

 

[hangontight]

stock - AC Delco

Been keeping the tank fairly low, and adding fresh gas now & then when taking it out (non-ethanol) I have a new fuel filter I will put on. I have an older MAF translator & LS1 sensor that I tried years ago when they 1st came out for the Buicks, I did not like the way it ran so I bought a new stock one, but I guess I could try it incase the MAF just took a dump. The car felt like it did when the hose 1st came of the throttle body but everything is on tight now?

Found my older LS1 MAF 3" sensor & MAF Translator plus(version 4.0). I wanted to install to see if the MAF sensor is bad, but before I do this I have some questions. As of now I can not find the original install instructions but I do remember I had to splice into the wiring up towards the firewall behind the coil pack, I hated to do this but at the time at had to. Looking at the newer version 6.25 the picture shows less wires coming out of the translator & looks like there is a "Plug & Play Adaptor" so no need to splice. Is my older version worth using? is there an adaptor for it? what is the difference between ver 4.0 & 6.25 see attached pictures.

View attachment 286041 View attachment 286044 View attachment 286045 View attachment 286046

For simplicity I would recommend the standard MAF translator, the plus add the ability to advance or retard timing which could be difficult to tune for some. Also if that's the MAF your using its an LT1 MAF and its plug and play with the 6.25 MAF translator- no adapter needed


Sent from my iPhone using Tapatalk

Ok to be be clear the MAF in the picture is an LT1 and I would be better off buying a new 6.25 version MAF sensor no wire splicing needed?

 

[hangontight]

Found my older LS1 MAF 3" sensor & MAF Translator plus(version 4.0). I wanted to install to see if the MAF sensor is bad, but before I do this I have some questions. As of now I can not find the original install instructions but I do remember I had to splice into the wiring up towards the firewall behind the coil pack, I hated to do this but at the time at had to. Looking at the newer version 6.25 the picture shows less wires coming out of the translator & looks like there is a "Plug & Play Adaptor" so no need to splice. Is my older version worth using? is there an adaptor for it? what is the difference between ver 4.0 & 6.25 see attached pictures.

View attachment 286041 View attachment 286044 View attachment 286045 View attachment 286046

Ok to be be clear the MAF in the picture is an LT1 and I would be better off buying a new 6.25 version MAF sensor no wire splicing needed?

Sorry I intended to say: I would be better off buying a new 6.25 version MAF "Translator" no wire splicing needed?

 

[Tom87GNX]

There's no splicing. Plug and play. Just make sure the switches inside are set to your chip.


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[hangontight]

There's no splicing. Plug and play. Just make sure the switches inside are set to your chip.


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ok Thanks, I need to order a new Turbo Tweak Chip & Injectors, to get up to date,