I just replaced the timing cover, timing gears, water pump, thermostat, hoses and belt. I reset the cam sensor using Casper's cam sensor tool, added fluids and primed her prior to start up.
1. She started up and (of course) the idle was erratic. Tlink displayed Malfunction Code 15 and I visually checked (what I believe to be) all of the harness connections. The twin pin connector on the front driver's side of the manifold was disconnected. I reconnected it, but it had no effect. Meanwhile, the coolant temps soared to 210*F in a span of 15 to 20 minutes and I shut her down in fear of overheating.
2. Additionally, my #s are all screwy. After attempting to reset and adjust the IAC several times, I've got no joy. I know the CTS malfunction has effect on fuel, timing, idle, etc., but man.
What's the likelyhood of my CTS going bad during a timing chain replacement?
------------------
87 GN (50K miles)
-TE-44, Dutt. necked IC, MSD 50's, THDP, ATR 2.5" exhaust, Boost/knock gauges, Tlink, Hotwired RA XPFP, BGC AFPR, Lubrant 93 chip, Translator Plus, LT1 MAF, ATR Bad Boy cold air kit, Vac brakes, Tie down strap
If you have a decent ohmmeter check the following.
Ground should be on the black wire in the harness make sure the pin is good and out all the way.
Measure accross the sensor itself with the harness unplugged.
Air temps. of 70 or so and the car not run in a while you should read about 3K ohms accross the sensor pins, do you?
Check on the voltage scale at the harness connector the yellow wire, it should read 5 volts to ground.
This is a start.
[This message has been edited by salvageV6 (edited April 27, 2002).]
Okay, Salvage...I let the car sit for 45 minutes after it's last spike of 207*F. It's matching the VDO gauge. The outside temp is about 70* (and rainy
). The engine was quite warm to the touch (I'd say borderline "hot") and this is what I got
1. Harness connection gives me 5.06V with the key on. 0.0V with key off.
2. The sensor read .64 Ohms on the 20K scale.
One more thing: During the last test drive, the coolant temp hovered around 165*F (on the road). When I brought back into the garage and idled, she shot up to 207*F before the fan kicked on. This brought it back down to 200*F and the fan shut off. My fan never runs after I shut the car down. I believe this is a different problem, but could be a contributing factor. Watcha got for me, Daddy-O?
[This message has been edited by *JOKER* (edited April 27, 2002).]
Thanks for the quick reply, Salvatore. The engine hasn't run since the last time I wrote, so it's pretty cool now. I went back and took another reading a few minutes ago and got 1.46 on the 2K scale of my digital multimeter. What's the story?
Sorry to hear about the trouble Ray. It can get frustrating at times. Can you tell if the water is circulating at all? Damn near sounds as though it's not...getting hot that quick. Are the radiator hoses hot?? Maybe the thermostat is stuck & not letting any/enough water get in.
You haven't noticed the hose collapsing at all??
The CTS code does sound suspicious though...seeing how it wasn't there before the work. I sound more confused than you huh?
You want answers not more questions?!!
I don't mind using the cts sensor off of my car if you decide you want to try it. Just let me know. I also have a spare ecm.
Since you have a "new" thermostat that would be suspect unless you boiled it in a pan of water on the stove and checked to see what temp. it opened at.
If the fan doesn't come on low speed near 160-180 the temps. will shoot up to 200 or so when the high speed fan kicks on.
If I read his post right, sounds like the thermostat is OK, since the engine runs down around 160 at highway speeds. However he did say that while sitting and letting it idle or slow driving the temps go up to around 200-207, this is an important clue, especially since he said the fan wouldn't come on until the temps got up over 200! Could be a couple of things.
1. The chip isn't commanding the fan on untill it hits stock fan settings (195).
2. The chip isn't commanding the fan on at all which could mean a fan relay problem, and what is turning it on is the high temp coolant switch, which kicks the fan on at around 205-210. This can be easilly confirmed by turning the A/C on with the engine idling. The fan should kick on when the A/C clutch engages.
Probably fan relay problems.
------------------
TurboDave & Kathy Huinker, mailto:TurboDave@turbobuicks.comTurboDave@turbobuicks.com</A> TurboD Racing
Lone Rock, WI 86 GN11.67@117.51(MM/MAF Xlator/Extender,MM BstC Boost Command,THDP,PTE44,CAS V2FM,MSD50's,9.5"vigilante 3500) 87 GN 12.95@105.50(Stock) 84 Z28 L69 01 Excursion LTD TTS"race" chip 7.3L PSD(power stroke diesel) Turbo 4X2 Pictures of my toys
Thermostat goes in front or the pointy part aiming out at you.
A persistant code 15 is a problem. I am sure you reset the ECM power but I would do it again and make sure your connections are good to the coolant sensor.
Next I would do Daves test and put the A/C on and see if the fan turns on at idle in the driveway in Park.
If it doesn't come on low speed I would swap the two small relays on the drivers side.
1. This morning, I tested the CTS again. ZERO ohms! Tlink, however, reads virtually the exact same as my VDO gauge. Wouldn't the ECM get a false reading from the CTS?!
2. I turned A/C on and the fan did not come on.
3. I swapped out relays, but the fan operated exactly the same.
You didn't break the coolant fan speed resistor when you were in there did you? It's the long white thing on the fan shroud just past the connector. A crack in it is ok as long as it's not broken.
Obviously theres no mechanical problems with the engine as it seems to run ok when driving but warms up at idle correct?
since the low speed fan is ECM controlled it should come on at a certian temp which will probably vary with chips. The high speed fan only comes on when coolant temp reaches 224'F or the A/C is on. Does your A/C work the fan only comes on after the compressor engauges through a pressure switch on the high press side.
My GN has a 160 t-stat in it and it will still run at 200'F until the fan comes on.
Did you run it with the can tool before and verify that it's not running the same?
207'F is no big deal unless your racing, remember water doesn't boil until 212 so your not going to hurt anything.
Didn't disturb any grounds on the front of the block
And this concludes my thinking and typing at the same time
The fan speed resistor is intact, but the wire connection on the passenger side has seen better days. Would that cause a code 15? I'll replace it tomorrow.
The fan does not come on when I turn on the A/C. It DOES come on around 207*F, though.
It always ran a little hot and the fan never operated (during my ownership) in low-speed mode.
My priority is in fixing the code 15 first, unless the fan issue is connected. I appreciate any suggestions on both.
Steve, the Tlink is accurately reflecting the same temperature that the VDO displays. Does the Tlink not read from the same source as the ECM?
Steve, I disconnected for the orange wire for a second and voila...code 15 gone. To state the obvious, I never reset the ECM after reconnecting the sensor
.
Salvage, It's too dark to work (and NVGs remove depth perception), so I'll try the 14 gauge wire trick tomorrow and repost.
the fan is a bit screwy sounding because it should pop on high as soon as you turn the ac on.
It sounds like the low speed relay is gone because it is not coming on at 160 or whereever Joe programs it.
But 207 sounds like the stock chip turn on. You ain't got the wrong chip installed, do you?
The circuits are pretty simple.
Low speed relay is the one with two red wires, a black/red, a brown, and two dark greens.
High speed relay has a red, a black/pink, a brown, and a dark green/yellow.
The brown wires come from the rlys fuse in the fuse block. I guess it is good since the fan will run.
The big relay is the delay relay.
With the key in the "run" position, it appears to me that if you ground the dark green wire coming from the low speed relay, the fan should run. If it does not, I would say the relay is bad. (this assumes the resistor is not burned out. Do Salvage's test and touch both sides of the resistor terminal...it should run both times-faster on one side than the other.)
Then if you ground the dark green/yellow wire on the high speed relay, the fan should run again, or that relay is bad.
The dark green/yellow wire runs to the coolant fan sensor which is on top of the intake between the alternator and the tb. You can pull that wire off the connector and ground it there, if you want to.
Steve.
Let's say the resistor is toasted.
You have a part number for a replacement 1.
Just curious, as it can break. I wouldn't mind having a replacement part around Just In Case.
Good old G.M.,eh Steve?That resistor has a value of .3 ohms @ 50 watts,if you want to replace it.I pulled the fan,checked the wiring,and mounted an aluminum bodied resistor.Easy to do.The resistor should be available from any electronics supply outlet.
------------------
Give em' hell!
This is an older thread, you may not receive a response, and could be reviving an old thread. Please consider creating a new thread.
Related Threads
?
?
?
?
?
Turbo Buick Forums
881.8K posts
20.5K members
Since 2000
A forum community dedicated to Buick Regal and Grand National owners and enthusiasts. Come join the discussion about performance, modifications, classifieds, troubleshooting, maintenance, and more!