weasie20 Posted September 9, 2005 Report Share Posted September 9, 2005 I've just gotten a 1991 DeVille from my father with 127,000 miles on it. No problems the first couple of weeks. Seemingly overnight, I now have a problem with hesitation. At first I thought I had gotten some bad gas. It was knocking quite a bit on acceleration. So, I refueled at a different station with higher octane and the knocking seemed to alleviate but this new problem developed. I'd describe it almost as if it's searching for a gear. You press on the gas from a standstill and the engine revs but accelerates very slowly. Once you're moving there doesn't seem to be a problem. It's only from a dead stop. The Service Engine light came on and I got two error codes, E40 and E90. I've been told neither of those codes would be the reason for this hesitation. Any ideas before I go and spend a zillion dollars at a dealership? Link to comment Share on other sites More sharing options...
adallak Posted September 9, 2005 Report Share Posted September 9, 2005 E90 - VCC Brake Switch Signal Problem. It has something to do with transmission, so I would address it first. To check VCC you should drive at some constant 50 mph and with your right foot on gas pedal touch the brake pedal with your left foot slightly to engage the brake switch. Watch RPM on DIC it should jump some 100-200 rpm. If it happens your VCC works properly. The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
Scotty Posted September 9, 2005 Report Share Posted September 9, 2005 Its possible that you are starting in second gear according to my 91 manual under lack of power, sluggish or spongy. There were a whole bunch of problems that can cause this, but combined with the E090 code that you are getting I focused on this: Check transmission operation for second gear starts, improper downshifts and proper VCC operation. The E090 code is: VCC/TCC Brake Switch/Park/neutral switch Input Circuit Problem I would hunt down that code E090 first. Check Fuse Number 1 in the interior relay center to see if it is blown Also check the brake switch circuit, connector loose, corroded, switch defective If you still have low rpm hesitation the E040 can cause hesitiation when the steering wheel is turned if the power steering pressure sensor is not functioning, the sensor sends a signal to the computer when the steering wheel is turned and the computer increases the RPM in response to the increased load caused by the steering pump in an effort to eliminate a possible stumble or stall turning the steering wheel at idle or on a turn. Link to comment Share on other sites More sharing options...
weasie20 Posted September 9, 2005 Author Report Share Posted September 9, 2005 Thanks guys. Any tips on a good on-line supplier I could investigate the price of that switch from? Link to comment Share on other sites More sharing options...
adallak Posted September 9, 2005 Report Share Posted September 9, 2005 Thanks guys. Any tips on a good on-line supplier I could investigate the price of that switch from? rockauto.com gmpartsdirect.com The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
Scotty Posted September 9, 2005 Report Share Posted September 9, 2005 Thanks guys. Any tips on a good on-line supplier I could investigate the price of that switch from? Don't just parts replace, you need to do some diagnostics. If you don't have a manual send me an email and I will scan some pages for you later today, Mike In the mean time check for loose/corroded wires at the brake switch Link to comment Share on other sites More sharing options...
KHE Posted September 9, 2005 Report Share Posted September 9, 2005 In addition to the above, the knocking on acceleration may be caused by the lack of EGR flow - remove the intake duct and hold the throttle body plade wide open. The two 1/2" tubes inside the manifold should not be caked up with carbon. Rod them out with a piece of coathanger wire all the way through to the manifold. Kevin '93 Fleetwood Brougham '05 Deville '04 Deville 2013 Silverado Z71 Link to comment Share on other sites More sharing options...
PAUL T Posted September 10, 2005 Report Share Posted September 10, 2005 Check the fuses, both inside and under the hood. I had this problem with my 92 Deville. I had a wire short out causing the VCC not to work. The wire was located on the passenger side in the front bottom corner under the front slash shield there was a wire that was rubbing on the frame and shorting out. Check the fuse and if it is blown check for this wire. Link to comment Share on other sites More sharing options...
Scotty Posted September 12, 2005 Report Share Posted September 12, 2005 Weasie, I sent 4 diagnostic pages on the E090 to the email you supplied me, Mike Link to comment Share on other sites More sharing options...
weasie20 Posted September 12, 2005 Author Report Share Posted September 12, 2005 Thanks all so much! Will check all the above! So glad I stumbled into this forum. What a wealth of knowledge! Link to comment Share on other sites More sharing options...
saizml Posted January 14, 2011 Report Share Posted January 14, 2011 ive got a 92 deville with the same problem (E90 code) can i get my hands on those diagnostic pages Link to comment Share on other sites More sharing options...
adallak Posted January 14, 2011 Report Share Posted January 14, 2011 ive got a 92 deville with the same problem (E90 code) can i get my hands on those diagnostic pages Do your brake lights turn on when you press the brake pedal and turn off when you release it? The saddest thing in life is wasted talent Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.