95 riviera sluggish

hi everybody. i have a 95 riviera with the series 1 3800 supercharged. here is my problam. my car has no take off power it is very sluggish in drive. ive also seen that when the ses light is on i have all my power back. but when the ses light is off its back to having no power. ive tryed plugging a reader up to it to c what codes it has but i get a link error. it will read for a min then say error. i replaced the alt and the car did good for about 2 days then messed up again . ive cleaned ground wires and all kinds of stuff. im just woundering if anybody else has had this probalm or can let me know what i can do to fix this. car only has 116k on it. and runs to good when ses light is on to be the trans or something major. seems electrical to me. would greatly appreciate the help

Hi Dustin. Have you ever changed the spark plugs & ignition wires? With your mileage I'd start there. Okay to use cheaper plugs like AutoLite, but find a set of AcDelco/Delphi wires, like those that came with the car. They're only about $35 on line (RockAuto.com). Good luck.

Take the car somewhere and have the SES code read. Probably will tell you what's wrong.

Welcome Dustin! There really are so many things that could cause the problem your having. You will have to find a scanner that can read OBD1.5 which the '95 Riv has. I own an Actron 9185 that will read it. I know there are others also, but I'm not sure which ones. Try Autozone. They may have one. I think if someone could read your codes for you, you will have a better idea of what to check. Good luck to ya, Dave

yes ive changed all the plugs and plug wires just when i changed the alt. i put acdelco plugs and delphi wires in it. ive also taken it to a couple diff ppl and everybodys reader says the same thing. link error

If the scan tools used are known to be OBD1.5 compatible, then you need to check the fuses on your car. The fuse for the ALDL could have blown.

Lots of folks have trouble reading OBD 1.5 codes. Common issue with '95s.

ok i will see where i can get wit that. so ur basic say that it is an obd1 computer wit an obd2 plug. this thing is been a pain the a!! i really apprentice everybodys help

Yeah, there's more info in this section: https://rivperformance.editboard.com/f14-series-i-scans-tuning

ok thanks everybody will c where i get wit this

ok i have another ? my riv has a lil 675 ca battery in it and i looked up how much 1 would cost and all there showing is a bigger battery wit 1000 ca battery. would that mess wit the car. i bought the car wit this probalm. ive only had it for about a week. but the guy that had it befor me had put a system in it and messed wit alot of stuff. just wondering since the car is all electric. im going to try and get it up to my work this friday and hook it up to the big obd computer and c if that will read it.

Once the car is started, the battery shouldn't matter, as long as it's in good condition. CCA are mainly for starting the car in the winter and when running lots of accessories (heated seats, defroster, etc.). Unless you are running a big stereo, or you only notice the problem when you turn everything on, I don't think this is causing your loss of power issue.

Get the group 79 battery the car calls for. Undo the mods until it is running ok so that you can actually find the problems.

The Riv will start with a toosmall baatttery but it won't keep parameters correct in the PCM. Then at some point the other headache is that since the PCM relies on sensor readings And the sensor readings are voltages if your battery is too small it won't keep the voltages high enough. Effectively, all the sensors then start BS-ing the PCM. If it is bad enough that the PCT can not determine spark advance correctly the car won't accelerate well. IIRC you wrote it runs better when the SES light comes on. That is because depending on what the fault is, the PCM will ignore the sensors and run the car using factory set defaults because **it no longer believes the sensors either. Then if it gets ok readings it goes back to using the sensors, and sets run parameters based on BS again.... and runs poopy.

So you are correct in surmising that you need to replace the battery. If you want to save money get the bath from a junkyard. People do not junk their cars over batteries that often and the junkyard techs can spot a good one a mile away. While you are at it snag the vent kit too.

If the $150.00 for the correct battery is not an issue then get the battery from a GM DEALER. Reason is the deco batteries are top shelf, built internally to take advantage of a feature on the riv. The riv will quick charge a battery if conditions are right. But if you put in a standard battery the overvoltage quickcharge is as likely as not to kill that battery.

If you get the correct group 79 battery elsewhere (walmart costco samsclub batterysplus etc) it will be OK but check a few GM dealers on price because some sell batteries cheap you will be shocked. Again BE SURE TO GET THE VENT KIT or else the ougassing fumes will rot the floor in the car (takes several months) and the battery will fall out the car floor. As likely as not the GM dealer (or for that matter the junkyard) will give you the ventkit and the other places wont likely have them but you can ask. Vent kit last time I bought one was around $20 at a dealer. It is a plastic contraption that snaps on the battery and a vent grommet in the car floor.

Albertj

ok heres an update. tried the big computer at my work. but got no were. tested some other stuff like the battery and the voltage for the alt etc. all seemed fine. messed wit the pcm. ses light would flash ever time i moved it. cleaned it got no were and ses light would not come on at all any more. so went and bought a new pcm and car works fine. ses light on but car hasent messed up for 2 days now. so i think when the other owner had a system in it wit a lil battery and a junk alt. he surged the pcm or somthing along them lines. going to try and find a code reader to read the ses but as of right now car runs good.

thanks everybody for the help. if wasnt for this site and the other posts i read i wouldve never thought to cheak the pcm

dustinb015 wrote:

thanks everybody for the help. if wasnt for this site and the other posts i read i wouldve never thought to cheak the pcm

You're welcome and sorry about the typos in my prior post. Sometimes I use a smartphone and don't type well.

Albertj

dustinb015 wrote:

ok heres an update. tried the big computer at my work. but got no were. tested some other stuff like the battery and the voltage for the alt etc. all seemed fine. messed wit the pcm. ses light would flash ever time i moved it. cleaned it got no were and ses light would not come on at all any more. so went and bought a new pcm and car works fine. ses light on but car hasent messed up for 2 days now. so i think when the other owner had a system in it wit a lil battery and a junk alt. he surged the pcm or somthing along them lines. going to try and find a code reader to read the ses but as of right now car runs good.

I have been having similar problems. I got a QBD1 error code when It read with a code reader but since then it hasnt worked on any code reader! Mine has had the ses light on for a year now. and I just recently am getting very poor milage like 12 mpg. I am wondering Where did you get another PCM from and how much was it? I think mine might need a new brain as well . Thanks for the info.

Do you guys notice any noise from the catalytic converter revving (you dont have to rev it too high to notice)in neutral or park? My cat became noisy quickly and made the car significantly slower. I gutted the cat and the car gained the lost power right back and then some, without too much extra noise. Ive never measured actual MPG but my car definitely goes farther on a tank of gas than before!

There are a few scanners that will read the 95's. i would ask around a Im sure someone will have one. Parts stores for some reason dont usually have scanners that can read the 95s so you might be best off seeing if a local shop might have one they would let you use!

th3fr4nchi5e wrote:

Do you guys notice any noise from the catalytic converter revving (you dont have to rev it too high to notice)in neutral or park? My cat became noisy quickly and made the car significantly slower. I gutted the cat and the car gained the lost power right back and then some, without too much extra noise. Ive never measured actual MPG but my car definitely goes farther on a tank of gas than before!

There are a few scanners that will read the 95's. i would ask around a Im sure someone will have one. Parts stores for some reason dont usually have scanners that can read the 95s so you might be best off seeing if a local shop might have one they would let you use!

Omg Yes!!!! I hear a big Tick Tick tick and its loudest right under the drivers side front tire... I figured it may be an exhaust leak/// So You're thinkin' that's my Catalytic converter?

Well a ticking from near the drivers side tire would most likely be an exhaust leak from the exhaust manifolds or EGR valve or piping. My car and the motor from my parts car had sticky EGR valves. This will set a code that can be read if you can find a compatible scanner! I took the EGR valve off mine and unstuck the actual valve and the code was gone and the car idled smoother and quieter.

The front exhaust manifold and crossover pipe on the 95s almost all crack with age which will cause a noticable ticking. This can be picked up as knock by the knock sensors and retard the timing. That would make the car very slow! I dont know that the cracks would be visible without pulling the manifold.
You can see what the cracks might look like here:
https://rivperformance.editboard.com/t10042-series-i-exhaust-manifolds

Keep us updated!

th3fr4nchi5e wrote:

Well a ticking from near the drivers side tire would most likely be an exhaust leak from the exhaust manifolds or EGR valve or piping. My car and the motor from my parts car had sticky EGR valves. This will set a code that can be read if you can find a compatible scanner! I took the EGR valve off mine and unstuck the actual valve and the code was gone and the car idled smoother and quieter.

The front exhaust manifold and crossover pipe on the 95s almost all crack with age which will cause a noticable ticking. This can be picked up as knock by the knock sensors and retard the timing. That would make the car very slow! I dont know that the cracks would be visible without pulling the manifold.
You can see what the cracks might look like here:
https://rivperformance.editboard.com/t10042-series-i-exhaust-manifolds

Keep us updated!

That does seem like the issue that it might be cracked it makes a loud ticking noise coming from underneath... I think my computer on the car is kinda screwy.. I haven't had any luck with any scanner reading it.. It just wont connect. I tell the stores that its an OBD 1 with an OBD 2 plug. I went to O'Reillys today and their scanner does both obd 1/2 and it didnt work... Also my car had been not running the best.. Sometime after its warm and hot it wont start.. Seems like it'll be running on 4 cylinders but after i let it cool off for an hour ill be ablke to start it and it'll run rough but then idle normal and i can drive...

The chance of your computer being screwy is slim. More likely than not, the problem lies in the scanner you are trying to read your car with. Many scanners will not read the '95 GM's with the OBD 2 plug. Regarding your issues with your car running poorly, I would guess you have either a plugged catalytic converter or a bad crank position sensor. If you have access to a digital thermometer, the converter is fairly easy to check. Run the car to warm it up. Check temp at inlet of converter and then the outlet. Outlet temp should be warmer. If inlet is warmer, you can be sure your cat is plugged.

Okay thanks! I'll get a hold of some friends and see if we can run some tests... Also Ive gotten a QDM 1 code or something when it was able to be read.. I got two errors... Speed sensor circuit and the QDM 1... I just saw somewhere that a qdm1 is a short somewhere causing some issues...

Every morning when I start it... It starts really rough then idles up.. It goes blub blub.. blubblub Vrrooomm idle...

Haha....

QDM is Quad driver module. I don't have much experience with those codes. Abaddon may be able to give you some advice on that.